MariaDbDatabaseMetaData.java

/*
MariaDB Client for Java

Copyright (c) 2012-2014 Monty Program Ab.

This library is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free
Software Foundation; either version 2.1 of the License, or (at your option)
any later version.

This library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
for more details.

You should have received a copy of the GNU Lesser General Public License along
with this library; if not, write to Monty Program Ab info@montyprogram.com.

This particular MariaDB Client for Java file is work
derived from a Drizzle-JDBC. Drizzle-JDBC file which is covered by subject to
the following copyright and notice provisions:

Copyright (c) 2009-2011, Marcus Eriksson

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
Redistributions of source code must retain the above copyright notice, this list
of conditions and the following disclaimer.

Redistributions in binary form must reproduce the above copyright notice, this
list of conditions and the following disclaimer in the documentation and/or
other materials provided with the distribution.

Neither the name of the driver nor the names of its contributors may not be
used to endorse or promote products derived from this software without specific
prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS  AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
OF SUCH DAMAGE.
*/

package org.mariadb.jdbc;

import org.mariadb.jdbc.internal.packet.dao.ColumnInformation;
import org.mariadb.jdbc.internal.queryresults.resultset.MariaSelectResultSet;
import org.mariadb.jdbc.internal.util.Utils;
import org.mariadb.jdbc.internal.util.constant.Version;
import org.mariadb.jdbc.internal.util.dao.Identifier;
import org.mariadb.jdbc.internal.MariaDbType;

import java.sql.*;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.List;

public class MariaDbDatabaseMetaData implements DatabaseMetaData {
    public static final String DRIVER_NAME = "MariaDB connector/J";
    private String url;
    private MariaDbConnection connection;
    private String databaseProductName = "MySQL";
    private String username;
    private boolean datePrecisionColumnExist = true;

    /**
     * Constructor.
     *
     * @param connection connection
     * @param user userName
     * @param url connection String url.
     */
    public MariaDbDatabaseMetaData(Connection connection, String user, String url) {
        this.connection = (MariaDbConnection) connection;
        this.username = user;
        this.url = url;
        this.connection.getProtocol().getServerVersion();
    }

    /* Remove length from column type spec,convert to uppercase,  e.g  bigint(10) unsigned becomes BIGINT UNSIGNED */
    static String columnTypeClause(int dataTypeMappingFlags, String columnName) {
        String upperCaseWithoutSize =  " UCASE(IF( " + columnName + " LIKE '%(%)%', CONCAT(SUBSTRING( " + columnName + ",1, LOCATE('(',"
                + columnName + ") - 1 ), SUBSTRING(" + columnName + ",1+locate(')'," + columnName + "))), "
                + columnName + "))";

        if ((dataTypeMappingFlags  & MariaSelectResultSet.TINYINT1_IS_BIT) > 0) {
            return " IF(" + columnName + " = 'tinyint(1)', 'BIT', " + upperCaseWithoutSize + ")";
        }
        return upperCaseWithoutSize;
    }

    /**
     * Retrieves a description of the primary key columns that are referenced by the given table's foreign key columns (the primary keys imported by a
     * table).  They are ordered by PKTABLE_CAT, PKTABLE_SCHEM, PKTABLE_NAME, and KEY_SEQ.
     * <P>Each primary key column description has the following columns: <OL> <LI><B>PKTABLE_CAT</B> String {@code =>} primary key table catalog being
     * imported (may be <code>null</code>) <LI><B>PKTABLE_SCHEM</B> String {@code =>} primary key table schema being imported (may be
     * <code>null</code>) <LI><B>PKTABLE_NAME</B> String {@code =>} primary key table name being imported <LI><B>PKCOLUMN_NAME</B> String {@code =>}
     * primary key column name being imported <LI><B>FKTABLE_CAT</B> String {@code =>} foreign key table catalog (may be <code>null</code>)
     * <LI><B>FKTABLE_SCHEM</B> String {@code =>} foreign key table schema (may be <code>null</code>) <LI><B>FKTABLE_NAME</B> String {@code =>}
     * foreign key table name <LI><B>FKCOLUMN_NAME</B> String {@code =>} foreign key column name <LI><B>KEY_SEQ</B> short {@code =>} sequence number
     * within a foreign key( a value of 1 represents the first column of the foreign key, a value of 2 would represent the second column within the
     * foreign key). <LI><B>UPDATE_RULE</B> short {@code =>} What happens to a foreign key when the primary key is updated: <UL> <LI> importedNoAction
     * - do not allow update of primary key if it has been imported <LI> importedKeyCascade - change imported key to agree with primary key update
     * <LI> importedKeySetNull - change imported key to <code>NULL</code> if its primary key has been updated <LI> importedKeySetDefault - change
     * imported key to default values if its primary key has been updated <LI> importedKeyRestrict - same as importedKeyNoAction (for ODBC 2.x
     * compatibility) </UL> <LI><B>DELETE_RULE</B> short {@code =>} What happens to the foreign key when primary is deleted. <UL> <LI>
     * importedKeyNoAction - do not allow delete of primary key if it has been imported <LI> importedKeyCascade - delete rows that import a deleted
     * key <LI> importedKeySetNull - change imported key to NULL if its primary key has been deleted <LI> importedKeyRestrict - same as
     * importedKeyNoAction (for ODBC 2.x compatibility) <LI> importedKeySetDefault - change imported key to default if its primary key has been
     * deleted </UL> <LI><B>FK_NAME</B> String {@code =>} foreign key name (may be <code>null</code>) <LI><B>PK_NAME</B> String {@code =>} primary key
     * name (may be <code>null</code>) <LI><B>DEFERRABILITY</B> short {@code =>} can the evaluation of foreign key constraints be deferred until
     * commit <UL> <LI> importedKeyInitiallyDeferred - see SQL92 for definition <LI> importedKeyInitiallyImmediate - see SQL92 for definition <LI>
     * importedKeyNotDeferrable - see SQL92 for definition </UL> </OL>
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schema a schema name; must match the schema name as it is stored in the database; "" retrieves those without a schema; <code>null</code>
     * means that the schema name should not be used to narrow the search
     * @param table a table name; must match the table name as it is stored in the database
     * @return <code>ResultSet</code> - each row is a primary key column description
     * @throws SQLException if a database access error occurs
     * @see #getExportedKeys
     */
    public ResultSet getImportedKeys(String catalog, String schema, String table) throws SQLException {

        // We avoid using information schema queries by default, because this appears to be an expensive
        // query (CONJ-41).
        if (table == null) {
            throw new SQLException("'table' parameter in getImportedKeys cannot be null");
        }

        if (catalog == null && connection.nullCatalogMeansCurrent) {
            /* Treat null catalog as current */
            catalog = "";
        }
        if (catalog == null) {
            return getImportedKeysUsingInformationSchema(catalog, schema, table);
        }

        if (catalog.equals("")) {
            catalog = connection.getCatalog();
            if (catalog == null || catalog.equals("")) {
                return getImportedKeysUsingInformationSchema(catalog, schema, table);
            }
        }

        try {
            return getImportedKeysUsingShowCreateTable(catalog, schema, table);
        } catch (Exception e) {
            // Likely, parsing failed, try out I_S query.
            return getImportedKeysUsingInformationSchema(catalog, schema, table);
        }
    }

    /**
     * Get imported keys.
     *
     * @param tableDef table definiation
     * @param tableName table name
     * @param catalog catalog
     * @param connection connection
     * @return resultset resultset
     * @throws ParseException exception
     */
    public static ResultSet getImportedKeys(String tableDef, String tableName, String catalog, MariaDbConnection connection) throws ParseException {
        String[] columnNames = {
                "PKTABLE_CAT", "PKTABLE_SCHEM", "PKTABLE_NAME",
                "PKCOLUMN_NAME", "FKTABLE_CAT", "FKTABLE_SCHEM",
                "FKTABLE_NAME", "FKCOLUMN_NAME", "KEY_SEQ",
                "UPDATE_RULE", "DELETE_RULE", "FK_NAME",
                "PK_NAME", "DEFERRABILITY"
        };
        MariaDbType[] columnTypes = {
                MariaDbType.VARCHAR, MariaDbType.NULL, MariaDbType.VARCHAR,
                MariaDbType.VARCHAR, MariaDbType.VARCHAR, MariaDbType.NULL,
                MariaDbType.VARCHAR, MariaDbType.VARCHAR, MariaDbType.SMALLINT,
                MariaDbType.SMALLINT, MariaDbType.SMALLINT, MariaDbType.VARCHAR,
                MariaDbType.NULL, MariaDbType.SMALLINT};

        String[] parts = tableDef.split("\n");

        List<String[]> data = new ArrayList<>();

        for (String part : parts) {
            part = part.trim();
            if (!part.startsWith("CONSTRAINT") && !part.contains("FOREIGN KEY")) {
                continue;
            }
            char[] partChar = part.toCharArray();

            Identifier constraintName = new Identifier();


            int pos = skipKeyword(partChar, 0, "CONSTRAINT");
            pos = parseIdentifier(partChar, pos, constraintName);
            pos = skipKeyword(partChar, pos, "FOREIGN KEY");
            List<Identifier> foreignKeyCols = new ArrayList<>();
            pos = parseIdentifierList(partChar, pos, foreignKeyCols);
            pos = skipKeyword(partChar, pos, "REFERENCES");
            Identifier pkTable = new Identifier();
            pos = parseIdentifier(partChar, pos, pkTable);
            List<Identifier> primaryKeyCols = new ArrayList<>();
            parseIdentifierList(partChar, pos, primaryKeyCols);
            if (primaryKeyCols.size() != foreignKeyCols.size()) {
                throw new ParseException(tableDef, 0);
            }
            int onUpdateReferenceAction = DatabaseMetaData.importedKeyRestrict;
            int onDeleteReferenceAction = DatabaseMetaData.importedKeyRestrict;


            for (String referenceAction : new String[]{"RESTRICT", "CASCADE", "SET NULL", "NO ACTION"}) {
                if (part.contains("ON UPDATE " + referenceAction)) {
                    onUpdateReferenceAction = getImportedKeyAction(referenceAction);
                }
                if (part.contains("ON DELETE " + referenceAction)) {
                    onDeleteReferenceAction = getImportedKeyAction(referenceAction);
                }
            }

            for (int i = 0; i < primaryKeyCols.size(); i++) {

                String[] row = new String[columnNames.length];
                row[0] = pkTable.schema;
                if (row[0] == null) {
                    row[0] = catalog;
                }
                row[1] = null;
                row[2] = pkTable.name;
                row[3] = primaryKeyCols.get(i).name;
                row[4] = catalog;
                row[5] = null;
                row[6] = tableName;
                row[7] = foreignKeyCols.get(i).name;
                row[8] = Integer.toString(i + 1);
                row[9] = Integer.toString(onUpdateReferenceAction);
                row[10] = Integer.toString(onDeleteReferenceAction);
                row[11] = constraintName.name;
                row[12] = null;
                row[13] = Integer.toString(DatabaseMetaData.importedKeyInitiallyImmediate);
                data.add(row);
            }
        }
        String[][] arr = data.toArray(new String[0][]);

         /* Sort array by PKTABLE_CAT, PKTABLE_NAME, and KEY_SEQ.*/
        Arrays.sort(arr, new Comparator<String[]>() {
            @Override
            public int compare(String[] row1, String[] row2) {
                int result = row1[0].compareTo(row2[0]);   //PKTABLE_CAT
                if (result == 0) {
                    result = row1[2].compareTo(row2[2]);   //PKTABLE_NAME
                    if (result == 0) {
                        result = row1[8].length() - row2[8].length();  // KEY_SEQ
                        if (result == 0) {
                            result = row1[8].compareTo(row2[8]);
                        }
                    }
                }
                return result;
            }
        });
        ResultSet ret = MariaSelectResultSet.createResultSet(columnNames, columnTypes, arr, connection.getProtocol());
        return ret;
    }

    // Extract identifier quoted string from input String.
    // Return new position, or -1 on error
    static int skipWhite(char[] part, int startPos) {
        for (int i = startPos; i < part.length; i++) {
            if (!Character.isWhitespace(part[i])) {
                return i;
            }
        }
        return part.length;
    }

    static int parseIdentifier(char[] part, int startPos, Identifier identifier) throws ParseException {
        int pos = skipWhite(part, startPos);
        if (part[pos] != '`') {
            throw new ParseException(new String(part), pos);
        }
        pos++;
        StringBuffer sb = new StringBuffer();
        int quotes = 0;
        for (; pos < part.length; pos++) {
            char ch = part[pos];
            if (ch == '`') {
                quotes++;
            } else {
                for (int j = 0; j < quotes / 2; j++) {
                    sb.append('`');
                }
                if (quotes % 2 == 1) {
                    if (ch == '.') {
                        if (identifier.schema != null) {
                            throw new ParseException(new String(part), pos);
                        }
                        identifier.schema = sb.toString();
                        return parseIdentifier(part, pos + 1, identifier);
                    }
                    identifier.name = sb.toString();
                    return pos;
                }
                quotes = 0;
                sb.append(ch);
            }
        }
        throw new ParseException(new String(part), startPos);
    }

    static int parseIdentifierList(char[] part, int startPos, List<Identifier> list) throws ParseException {
        int pos = skipWhite(part, startPos);
        if (part[pos] != '(') {
            throw new ParseException(new String(part), pos);
        }
        pos++;
        for (; ; ) {
            pos = skipWhite(part, pos);
            char ch = part[pos];
            switch (ch) {
                case ')':
                    return pos + 1;
                case '`':
                    Identifier id = new Identifier();
                    pos = parseIdentifier(part, pos, id);
                    list.add(id);
                    break;
                case ',':
                    pos++;
                    break;
                default:
                    throw new ParseException(new String(part, startPos, part.length - startPos), startPos);
            }
        }
    }

    static int skipKeyword(char[] part, int startPos, String keyword) throws ParseException {
        int pos = skipWhite(part, startPos);
        for (int i = 0; i < keyword.length(); i++, pos++) {
            if (part[pos] != keyword.charAt(i)) {
                throw new ParseException(new String(part), pos);
            }
        }
        return pos;
    }

    static int getImportedKeyAction(String actionKey) {
        if (actionKey == null) {
            return DatabaseMetaData.importedKeyRestrict;
        }
        if (actionKey.equals("NO ACTION")) {
            return DatabaseMetaData.importedKeyNoAction;
        }
        if (actionKey.equals("CASCADE")) {
            return DatabaseMetaData.importedKeyCascade;
        }
        if (actionKey.equals("SET NULL")) {
            return DatabaseMetaData.importedKeySetNull;
        }
        if (actionKey.equals("SET DEFAULT")) {
            return DatabaseMetaData.importedKeySetDefault;
        }
        if (actionKey.equals("RESTRICT")) {
            return DatabaseMetaData.importedKeyRestrict;
        }
        throw new AssertionError("should not happen");
    }


    private String dataTypeClause(String fullTypeColumnName) {
        return
                " CASE data_type"
                        + " WHEN 'bit' THEN " + Types.BIT
                        + " WHEN 'tinyblob' THEN " + Types.VARBINARY
                        + " WHEN 'mediumblob' THEN " + Types.LONGVARBINARY
                        + " WHEN 'longblob' THEN " + Types.LONGVARBINARY
                        + " WHEN 'blob' THEN " + Types.LONGVARBINARY
                        + " WHEN 'tinytext' THEN " + Types.VARCHAR
                        + " WHEN 'mediumtext' THEN " + Types.LONGVARCHAR
                        + " WHEN 'longtext' THEN " + Types.LONGVARCHAR
                        + " WHEN 'text' THEN " + Types.LONGVARCHAR
                        + " WHEN 'date' THEN " + Types.DATE
                        + " WHEN 'datetime' THEN " + Types.TIMESTAMP
                        + " WHEN 'decimal' THEN " + Types.DECIMAL
                        + " WHEN 'double' THEN " + Types.DOUBLE
                        + " WHEN 'enum' THEN " + Types.VARCHAR
                        + " WHEN 'float' THEN " + Types.REAL
                        + " WHEN 'int' THEN IF( " + fullTypeColumnName + " like '%unsigned%', " + Types.INTEGER + "," + Types.INTEGER + ")"
                        + " WHEN 'bigint' THEN " + Types.BIGINT
                        + " WHEN 'mediumint' THEN " + Types.INTEGER
                        + " WHEN 'null' THEN " + Types.NULL
                        + " WHEN 'set' THEN " + Types.VARCHAR
                        + " WHEN 'smallint' THEN IF( " + fullTypeColumnName + " like '%unsigned%', " + Types.SMALLINT + "," + Types.SMALLINT + ")"
                        + " WHEN 'varchar' THEN " + Types.VARCHAR
                        + " WHEN 'varbinary' THEN " + Types.VARBINARY
                        + " WHEN 'char' THEN " + Types.CHAR
                        + " WHEN 'binary' THEN " + Types.BINARY
                        + " WHEN 'time' THEN " + Types.TIME
                        + " WHEN 'timestamp' THEN " + Types.TIMESTAMP
                        + " WHEN 'tinyint' THEN "
                        + (((connection.getProtocol().getDataTypeMappingFlags() & MariaSelectResultSet.TINYINT1_IS_BIT) == 0)
                        ? Types.TINYINT : "IF(" + fullTypeColumnName + "='tinyint(1)'," + Types.BIT + "," + Types.TINYINT + ") ")
                        + " WHEN 'year' THEN "
                        + (((connection.getProtocol().getDataTypeMappingFlags() & MariaSelectResultSet.YEAR_IS_DATE_TYPE) == 0)
                        ? Types.SMALLINT : Types.DATE)
                        + " ELSE " + Types.OTHER
                        + " END ";
    }

    private ResultSet executeQuery(String sql) throws SQLException {
        MariaSelectResultSet rs = (MariaSelectResultSet) connection.createStatement().executeQuery(sql);
        rs.setStatement(null); // bypass Hibernate statement tracking (CONJ-49)
        rs.setReturnTableAlias(true);
        return rs;
    }

    private String escapeQuote(String value) {
        if (value == null) {
            return "NULL";
        }
        return "'" + Utils.escapeString(value, connection.noBackslashEscapes) + "'";
    }

    /**
     * Generate part of the information schema query that restricts catalog names In the driver, catalogs is the equivalent to MySQL schemas.
     *
     * @param columnName - column name in the information schema table
     * @param catalog - catalog name.
     * This driver does not (always) follow JDBC standard for following special values, due to ConnectorJ compatibility
     * 1. empty string ("") - matches current catalog (i.e database).JDBC standard says only tables without catalog should be returned - such tables
     * do not exist in MySQL. If there is no current catalog, then empty string matches any catalog.
     * 2. null  - if nullCatalogMeansCurrent=true (which is the default), then the handling is the same as for "" . i.e return current catalog.
     * JDBC-conforming way would be to match any catalog with null parameter. This can be switched with nullCatalogMeansCurrent=false in the
     * connection URL.
     * @return part of SQL query ,that restricts search for the catalog.
     */
    String catalogCond(String columnName, String catalog) {
        if (catalog == null && connection.nullCatalogMeansCurrent) {
            /* Treat null catalog as current */
            catalog = "";
        }

        if (catalog == null) {
            return "(1 = 1)";
        }
        if (catalog.equals("")) {
            return "(ISNULL(database()) OR (" + columnName + " = database()))";
        }
        return "(" + columnName + " = " + escapeQuote(catalog) + ")";

    }

    // Helper to generate  information schema queries with "like" or "equals" condition (typically  on table name)
    String patternCond(String columnName, String tableName) {
        if (tableName == null) {
            return "(1 = 1)";
        }
        String predicate = (tableName.indexOf('%') == -1 && tableName.indexOf('_') == -1) ? "=" : "LIKE";
        return "(" + columnName + " " + predicate + " '" + Utils.escapeString(tableName, true) + "')";
    }

    /**
     * Retrieves a description of the given table's primary key columns.  They are ordered by COLUMN_NAME.
     * <P>Each primary key column description has the following columns: <OL> <LI><B>TABLE_CAT</B> String {@code =>} table catalog (may be
     * <code>null</code>) <LI><B>TABLE_SCHEM</B> String {@code =>} table schema (may be <code>null</code>) <LI><B>TABLE_NAME</B> String {@code =>}
     * table name <LI><B>COLUMN_NAME</B> String {@code =>} column name <LI><B>KEY_SEQ</B> short {@code =>} sequence number within primary key( a value
     * of 1 represents the first column of the primary key, a value of 2 would represent the second column within the primary key). <LI><B>PK_NAME</B>
     * String {@code =>} primary key name (may be <code>null</code>) </OL>
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schema a schema name; must match the schema name as it is stored in the database; "" retrieves those without a schema; <code>null</code>
     * means that the schema name should not be used to narrow the search
     * @param table a table name; must match the table name as it is stored in the database
     * @return <code>ResultSet</code> - each row is a primary key column description
     * @throws SQLException if a database access error occurs
     */
    public ResultSet getPrimaryKeys(String catalog, String schema, String table) throws SQLException {
        String sql =
                "SELECT A.TABLE_SCHEMA TABLE_CAT, NULL TABLE_SCHEM, A.TABLE_NAME, A.COLUMN_NAME, B.SEQ_IN_INDEX KEY_SEQ, NULL PK_NAME "
                        + " FROM INFORMATION_SCHEMA.COLUMNS A, INFORMATION_SCHEMA.STATISTICS B"
                        + " WHERE A.COLUMN_KEY='pri' AND B.INDEX_NAME='PRIMARY' "
                        + " AND "
                        + catalogCond("A.TABLE_SCHEMA", catalog)
                        + " AND "
                        + catalogCond("B.TABLE_SCHEMA", catalog)
                        + " AND "
                        + patternCond("A.TABLE_NAME", table)
                        + " AND "
                        + patternCond("B.TABLE_NAME", table)
                        + " AND A.TABLE_SCHEMA = B.TABLE_SCHEMA AND A.TABLE_NAME = B.TABLE_NAME AND A.COLUMN_NAME = B.COLUMN_NAME "
                        + " ORDER BY A.COLUMN_NAME";

        return executeQuery(sql);

    }

    /**
     * Maps standard table types to mysql ones - helper since table type is never "table" in mysql, it is "base table"
     *
     * @param tableType the table type defined by user
     * @return the internal table type.
     */
    private String mapTableTypes(String tableType) {
        if (tableType.equals("TABLE")) {
            return "BASE TABLE";
        }
        return tableType;
    }

    /**
     * Retrieves a description of the tables available in the given catalog. Only table descriptions matching the catalog, schema, table name and type
     * criteria are returned.  They are ordered by <code>TABLE_TYPE</code>, <code>TABLE_CAT</code>, <code>TABLE_SCHEM</code> and
     * <code>TABLE_NAME</code>.
     * Each table description has the following columns: <OL> <LI><B>TABLE_CAT</B> String {@code =>} table catalog (may be <code>null</code>)
     * <LI><B>TABLE_SCHEM</B> String {@code =>} table schema (may be <code>null</code>) <LI><B>TABLE_NAME</B> String {@code =>} table name
     * <LI><B>TABLE_TYPE</B> String {@code =>} table type.  Typical types are "TABLE", "VIEW", "SYSTEM TABLE", "GLOBAL TEMPORARY", "LOCAL TEMPORARY",
     * "ALIAS", "SYNONYM". <LI><B>REMARKS</B> String {@code =>} explanatory comment on the table <LI><B>TYPE_CAT</B> String {@code =>} the types
     * catalog (may be <code>null</code>) <LI><B>TYPE_SCHEM</B> String {@code =>} the types schema (may be <code>null</code>) <LI><B>TYPE_NAME</B>
     * String {@code =>} type name (may be <code>null</code>) <LI><B>SELF_REFERENCING_COL_NAME</B> String {@code =>} name of the designated
     * "identifier" column of a typed table (may be <code>null</code>) <LI><B>REF_GENERATION</B> String {@code =>} specifies how values in
     * SELF_REFERENCING_COL_NAME are created. Values are "SYSTEM", "USER", "DERIVED". (may be <code>null</code>) </OL>
     * <P><B>Note:</B> Some databases may not return information for all tables.
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schemaPattern a schema name pattern; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param tableNamePattern a table name pattern; must match the table name as it is stored in the database
     * @param types a list of table types, which must be from the list of table types returned from {@link #getTableTypes},to include;
     * <code>null</code> returns all types
     * @return <code>ResultSet</code> - each row is a table description
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     */
    public ResultSet getTables(String catalog, String schemaPattern, String tableNamePattern, String[] types)
            throws SQLException {

        String sql =
                "SELECT TABLE_SCHEMA TABLE_CAT, NULL  TABLE_SCHEM,  TABLE_NAME, IF(TABLE_TYPE='BASE TABLE', 'TABLE', TABLE_TYPE) as TABLE_TYPE,"
                        + " TABLE_COMMENT REMARKS, NULL TYPE_CAT, NULL TYPE_SCHEM, NULL TYPE_NAME, NULL SELF_REFERENCING_COL_NAME, "
                        + " NULL REF_GENERATION"
                        + " FROM INFORMATION_SCHEMA.TABLES "
                        + " WHERE "
                        + catalogCond("TABLE_SCHEMA", catalog)
                        + " AND "
                        + patternCond("TABLE_NAME", tableNamePattern);

        if (types != null && types.length > 0) {
            sql += " AND TABLE_TYPE IN (";
            for (int i = 0; i < types.length; i++) {
                if (types[i] == null) {
                    continue;
                }
                String type = escapeQuote(mapTableTypes(types[i]));
                if (i == types.length - 1) {
                    sql += type + ")";
                } else {
                    sql += type + ",";
                }
            }
        }

        sql += " ORDER BY TABLE_TYPE, TABLE_SCHEMA, TABLE_NAME";

        return executeQuery(sql);
    }

    /**
     * Retrieves a description of table columns available in the specified catalog.
     * <P>Only column descriptions matching the catalog, schema, table and column name criteria are returned.  They are ordered by
     * <code>TABLE_CAT</code>,<code>TABLE_SCHEM</code>, <code>TABLE_NAME</code>, and <code>ORDINAL_POSITION</code>.
     * <P>Each column description has the following columns: <OL> <LI><B>TABLE_CAT</B> String {@code =>} table catalog (may be <code>null</code>)
     * <LI><B>TABLE_SCHEM</B> String {@code =>} table schema (may be <code>null</code>) <LI><B>TABLE_NAME</B> String {@code =>} table name
     * <LI><B>COLUMN_NAME</B> String {@code =>} column name <LI><B>DATA_TYPE</B> int {@code =>} SQL type from java.sql.Types <LI><B>TYPE_NAME</B>
     * String {@code =>} Data source dependent type name, for a UDT the type name is fully qualified <LI><B>COLUMN_SIZE</B> int {@code =>} column
     * size. <LI><B>BUFFER_LENGTH</B> is not used. <LI><B>DECIMAL_DIGITS</B> int {@code =>} the number of fractional digits. Null is returned for data
     * types where DECIMAL_DIGITS is not applicable. <LI><B>NUM_PREC_RADIX</B> int {@code =>} Radix (typically either 10 or 2) <LI><B>NULLABLE</B> int
     * {@code =>} is NULL allowed. <UL> <LI> columnNoNulls - might not allow <code>NULL</code> values <LI> columnNullable - definitely allows
     * <code>NULL</code> values <LI> columnNullableUnknown - nullability unknown </UL> <LI><B>REMARKS</B> String {@code =>} comment describing column
     * (may be <code>null</code>) <LI><B>COLUMN_DEF</B> String {@code =>} default value for the column, which should be interpreted as a string when
     * the value is enclosed in single quotes (may be <code>null</code>) <LI><B>SQL_DATA_TYPE</B> int {@code =>} unused <LI><B>SQL_DATETIME_SUB</B>
     * int {@code =>} unused <LI><B>CHAR_OCTET_LENGTH</B> int {@code =>} for char types the maximum number of bytes in the column
     * <LI><B>ORDINAL_POSITION</B> int {@code =>} index of column in table (starting at 1) <LI><B>IS_NULLABLE</B> String  {@code =>} ISO rules are
     * used to determine the nullability for a column. <UL> <LI> YES           --- if the column can include NULLs <LI> NO            --- if the
     * column cannot include NULLs <LI> empty string  --- if the nullability for the column is unknown </UL> <LI><B>SCOPE_CATALOG</B> String {@code
     * =>} catalog of table that is the scope of a reference attribute (<code>null</code> if DATA_TYPE isn't REF) <LI><B>SCOPE_SCHEMA</B> String
     * {@code =>} schema of table that is the scope of a reference attribute (<code>null</code> if the DATA_TYPE isn't REF) <LI><B>SCOPE_TABLE</B>
     * String {@code =>} table name that this the scope of a reference attribute (<code>null</code> if the DATA_TYPE isn't REF)
     * <LI><B>SOURCE_DATA_TYPE</B> short {@code =>} source type of a distinct type or user-generated Ref type, SQL type from java.sql.Types
     * (<code>null</code> if DATA_TYPE isn't DISTINCT or user-generated REF) <LI><B>IS_AUTOINCREMENT</B> String  {@code =>} Indicates whether this
     * column is auto incremented <UL> <LI> YES           --- if the column is auto incremented <LI> NO            --- if the column is not auto
     * incremented <LI> empty string  --- if it cannot be determined whether the column is auto incremented </UL> <LI><B>IS_GENERATEDCOLUMN</B> String
     * {@code =>} Indicates whether this is a generated column <UL> <LI> YES           --- if this a generated column <LI> NO            --- if this
     * not a generated column <LI> empty string  --- if it cannot be determined whether this is a generated column </UL> </OL>
     * <p>The COLUMN_SIZE column specifies the column size for the given column. For numeric data, this is the maximum precision.  For character data,
     * this is the length in characters. For datetime datatypes, this is the length in characters of the String representation (assuming the maximum
     * allowed precision of the fractional seconds component). For binary data, this is the length in bytes.  For the ROWID datatype, this is the
     * length in bytes. Null is returned for data types where the column size is not applicable.
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schemaPattern a schema name pattern; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param tableNamePattern a table name pattern; must match the table name as it is stored in the database
     * @param columnNamePattern a column name pattern; must match the column name as it is stored in the database
     * @return <code>ResultSet</code> - each row is a column description
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     */
    public ResultSet getColumns(String catalog, String schemaPattern, String tableNamePattern, String columnNamePattern)
            throws SQLException {
        String sql = "SELECT TABLE_SCHEMA TABLE_CAT, NULL TABLE_SCHEM, TABLE_NAME, COLUMN_NAME,"
                + dataTypeClause("COLUMN_TYPE") + " DATA_TYPE,"
                + columnTypeClause(connection.getProtocol().getDataTypeMappingFlags(), "COLUMN_TYPE") + " TYPE_NAME, "
                + " CASE DATA_TYPE"
                + "  WHEN 'time' THEN "
                    + (datePrecisionColumnExist ? "IF(DATETIME_PRECISION = 0, 10, CAST(11 + DATETIME_PRECISION as signed integer))" : "10")
                + "  WHEN 'date' THEN 10"
                + "  WHEN 'datetime' THEN "
                    + (datePrecisionColumnExist ? "IF(DATETIME_PRECISION = 0, 19, CAST(20 + DATETIME_PRECISION as signed integer))" : "19")
                + "  WHEN 'timestamp' THEN "
                    + (datePrecisionColumnExist ? "IF(DATETIME_PRECISION = 0, 19, CAST(20 + DATETIME_PRECISION as signed integer))" : "19")
                + "  ELSE "
                + "  IF(NUMERIC_PRECISION IS NULL, LEAST(CHARACTER_MAXIMUM_LENGTH," + Integer.MAX_VALUE + "), NUMERIC_PRECISION) "
                + " END"
                + " COLUMN_SIZE, 65535 BUFFER_LENGTH, NUMERIC_SCALE DECIMAL_DIGITS,"
                + " 10 NUM_PREC_RADIX, IF(IS_NULLABLE = 'yes',1,0) NULLABLE,COLUMN_COMMENT REMARKS,"
                + " COLUMN_DEFAULT COLUMN_DEF, 0 SQL_DATA_TYPE, 0 SQL_DATETIME_SUB,  "
                + " LEAST(CHARACTER_OCTET_LENGTH," + Integer.MAX_VALUE + ") CHAR_OCTET_LENGTH,"
                + " ORDINAL_POSITION, IS_NULLABLE, NULL SCOPE_CATALOG, NULL SCOPE_SCHEMA, NULL SCOPE_TABLE, NULL SOURCE_DATA_TYPE,"
                + " IF(EXTRA = 'auto_increment','YES','NO') IS_AUTOINCREMENT, "
                + " IF(EXTRA in ('VIRTUAL', 'PERSISTENT', 'VIRTUAL GENERATED', 'STORED GENERATED') ,'YES','NO') IS_GENERATEDCOLUMN "
                + " FROM INFORMATION_SCHEMA.COLUMNS  WHERE "
                + catalogCond("TABLE_SCHEMA", catalog)
                + " AND "
                + patternCond("TABLE_NAME", tableNamePattern)
                + " AND "
                + patternCond("COLUMN_NAME", columnNamePattern)
                + " ORDER BY TABLE_CAT, TABLE_SCHEM, TABLE_NAME, ORDINAL_POSITION";

        try {
            return executeQuery(sql);
        } catch (SQLException sqlException) {
            if (sqlException.getMessage().contains("Unknown column 'DATETIME_PRECISION'")) {
                datePrecisionColumnExist = false;
                return getColumns(catalog, schemaPattern, tableNamePattern, columnNamePattern);
            }
            throw sqlException;
        }

    }

    /**
     * Retrieves a description of the foreign key columns that reference the given table's primary key columns (the foreign keys exported by a table).
     * They are ordered by FKTABLE_CAT, FKTABLE_SCHEM, FKTABLE_NAME, and KEY_SEQ.
     * <P>Each foreign key column description has the following columns: <OL> <LI><B>PKTABLE_CAT</B> String {@code =>} primary key table catalog (may
     * be <code>null</code>) <LI><B>PKTABLE_SCHEM</B> String {@code =>} primary key table schema (may be <code>null</code>) <LI><B>PKTABLE_NAME</B>
     * String {@code =>} primary key table name <LI><B>PKCOLUMN_NAME</B> String {@code =>} primary key column name <LI><B>FKTABLE_CAT</B> String
     * {@code =>} foreign key table catalog (may be <code>null</code>) being exported (may be <code>null</code>) <LI><B>FKTABLE_SCHEM</B> String
     * {@code =>} foreign key table schema (may be <code>null</code>) being exported (may be <code>null</code>) <LI><B>FKTABLE_NAME</B> String {@code
     * =>} foreign key table name being exported <LI><B>FKCOLUMN_NAME</B> String {@code =>} foreign key column name being exported <LI><B>KEY_SEQ</B>
     * short {@code =>} sequence number within foreign key( a value of 1 represents the first column of the foreign key, a value of 2 would represent
     * the second column within the foreign key). <LI><B>UPDATE_RULE</B> short {@code =>} What happens to foreign key when primary is updated: <UL>
     * <LI> importedNoAction - do not allow update of primary key if it has been imported <LI> importedKeyCascade - change imported key to agree with
     * primary key update <LI> importedKeySetNull - change imported key to <code>NULL</code> if its primary key has been updated <LI>
     * importedKeySetDefault - change imported key to default values if its primary key has been updated <LI> importedKeyRestrict - same as
     * importedKeyNoAction (for ODBC 2.x compatibility) </UL> <LI><B>DELETE_RULE</B> short {@code =>} What happens to the foreign key when primary is
     * deleted. <UL> <LI> importedKeyNoAction - do not allow delete of primary key if it has been imported <LI> importedKeyCascade - delete rows that
     * import a deleted key <LI> importedKeySetNull - change imported key to <code>NULL</code> if its primary key has been deleted <LI>
     * importedKeyRestrict - same as importedKeyNoAction (for ODBC 2.x compatibility) <LI> importedKeySetDefault - change imported key to default if
     * its primary key has been deleted </UL> <LI><B>FK_NAME</B> String {@code =>} foreign key name (may be <code>null</code>) <LI><B>PK_NAME</B>
     * String {@code =>} primary key name (may be <code>null</code>) <LI><B>DEFERRABILITY</B> short {@code =>} can the evaluation of foreign key
     * constraints be deferred until commit <UL> <LI> importedKeyInitiallyDeferred - see SQL92 for definition <LI> importedKeyInitiallyImmediate - see
     * SQL92 for definition <LI> importedKeyNotDeferrable - see SQL92 for definition </UL> </OL>
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in this database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schema a schema name; must match the schema name as it is stored in the database; "" retrieves those without a schema; <code>null</code>
     * means that the schema name should not be used to narrow the search
     * @param table a table name; must match the table name as it is stored in this database
     * @return a <code>ResultSet</code> object in which each row is a foreign key column description
     * @throws SQLException if a database access error occurs
     * @see #getImportedKeys
     */
    public ResultSet getExportedKeys(String catalog, String schema, String table) throws SQLException {
        if (table == null) {
            throw new SQLException("'table' parameter in getExportedKeys cannot be null");
        }
        String sql =
                "SELECT KCU.REFERENCED_TABLE_SCHEMA PKTABLE_CAT, NULL PKTABLE_SCHEM,  KCU.REFERENCED_TABLE_NAME PKTABLE_NAME,"
                        + " KCU.REFERENCED_COLUMN_NAME PKCOLUMN_NAME, KCU.TABLE_SCHEMA FKTABLE_CAT, NULL FKTABLE_SCHEM, "
                        + " KCU.TABLE_NAME FKTABLE_NAME, KCU.COLUMN_NAME FKCOLUMN_NAME, KCU.POSITION_IN_UNIQUE_CONSTRAINT KEY_SEQ,"
                        + " CASE update_rule "
                        + "   WHEN 'RESTRICT' THEN 1"
                        + "   WHEN 'NO ACTION' THEN 3"
                        + "   WHEN 'CASCADE' THEN 0"
                        + "   WHEN 'SET NULL' THEN 2"
                        + "   WHEN 'SET DEFAULT' THEN 4"
                        + " END UPDATE_RULE,"
                        + " CASE DELETE_RULE"
                        + "  WHEN 'RESTRICT' THEN 1"
                        + "  WHEN 'NO ACTION' THEN 3"
                        + "  WHEN 'CASCADE' THEN 0"
                        + "  WHEN 'SET NULL' THEN 2"
                        + "  WHEN 'SET DEFAULT' THEN 4"
                        + " END DELETE_RULE,"
                        + " RC.CONSTRAINT_NAME FK_NAME,"
                        + " NULL PK_NAME,"
                        + " 6 DEFERRABILITY"
                        + " FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU"
                        + " INNER JOIN INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS RC"
                        + " ON KCU.CONSTRAINT_SCHEMA = RC.CONSTRAINT_SCHEMA"
                        + " AND KCU.CONSTRAINT_NAME = RC.CONSTRAINT_NAME"
                        + " WHERE "
                        + catalogCond("KCU.REFERENCED_TABLE_SCHEMA", catalog)
                        + " AND "
                        + " KCU.REFERENCED_TABLE_NAME = " + escapeQuote(table)
                        + " ORDER BY FKTABLE_CAT, FKTABLE_SCHEM, FKTABLE_NAME, KEY_SEQ";

        return executeQuery(sql);
    }

    /**
     * GetImportedKeysUsingInformationSchema.
     *
     * @param catalog catalog
     * @param schema schema
     * @param table table
     * @return resultset
     * @throws SQLException exception
     */
    public ResultSet getImportedKeysUsingInformationSchema(String catalog, String schema, String table) throws SQLException {
        if (table == null) {
            throw new SQLException("'table' parameter in getImportedKeys cannot be null");
        }
        String sql =
                "SELECT KCU.REFERENCED_TABLE_SCHEMA PKTABLE_CAT, NULL PKTABLE_SCHEM,  KCU.REFERENCED_TABLE_NAME PKTABLE_NAME,"
                        + " KCU.REFERENCED_COLUMN_NAME PKCOLUMN_NAME, KCU.TABLE_SCHEMA FKTABLE_CAT, NULL FKTABLE_SCHEM, "
                        + " KCU.TABLE_NAME FKTABLE_NAME, KCU.COLUMN_NAME FKCOLUMN_NAME, KCU.POSITION_IN_UNIQUE_CONSTRAINT KEY_SEQ,"
                        + " CASE update_rule "
                        + "   WHEN 'RESTRICT' THEN 1"
                        + "   WHEN 'NO ACTION' THEN 3"
                        + "   WHEN 'CASCADE' THEN 0"
                        + "   WHEN 'SET NULL' THEN 2"
                        + "   WHEN 'SET DEFAULT' THEN 4"
                        + " END UPDATE_RULE,"
                        + " CASE DELETE_RULE"
                        + "  WHEN 'RESTRICT' THEN 1"
                        + "  WHEN 'NO ACTION' THEN 3"
                        + "  WHEN 'CASCADE' THEN 0"
                        + "  WHEN 'SET NULL' THEN 2"
                        + "  WHEN 'SET DEFAULT' THEN 4"
                        + " END DELETE_RULE,"
                        + " RC.CONSTRAINT_NAME FK_NAME,"
                        + " NULL PK_NAME,"
                        + " 6 DEFERRABILITY"
                        + " FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU"
                        + " INNER JOIN INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS RC"
                        + " ON KCU.CONSTRAINT_SCHEMA = RC.CONSTRAINT_SCHEMA"
                        + " AND KCU.CONSTRAINT_NAME = RC.CONSTRAINT_NAME"
                        + " WHERE "
                        + catalogCond("KCU.TABLE_SCHEMA", catalog)
                        + " AND "
                        + " KCU.TABLE_NAME = " + escapeQuote(table)
                        + " ORDER BY PKTABLE_CAT, PKTABLE_SCHEM, PKTABLE_NAME, KEY_SEQ";

        return executeQuery(sql);
    }

    /**
     * GetImportedKeysUsingShowCreateTable.
     *
     * @param catalog catalog
     * @param schema schema
     * @param table table
     * @return resultset
     * @throws SQLException exception
     */
    public ResultSet getImportedKeysUsingShowCreateTable(String catalog, String schema, String table) throws Exception {

        if (catalog == null || catalog.equals("")) {
            throw new IllegalArgumentException("catalog");
        }

        if (table == null || table.equals("")) {
            throw new IllegalArgumentException("table");
        }
        ResultSet rs = connection.createStatement().executeQuery("SHOW CREATE TABLE "
                + MariaDbConnection.quoteIdentifier(catalog) + "." + MariaDbConnection.quoteIdentifier(table));
        rs.next();
        String tableDef = rs.getString(2);
        return MariaDbDatabaseMetaData.getImportedKeys(tableDef, table, catalog, connection);
    }

    /**
     * Retrieves a description of a table's optimal set of columns that uniquely identifies a row. They are ordered by SCOPE.
     * <P>Each column description has the following columns: <OL> <LI><B>SCOPE</B> short {@code =>} actual scope of result <UL> <LI> bestRowTemporary
     * - very temporary, while using row <LI> bestRowTransaction - valid for remainder of current transaction <LI> bestRowSession - valid for
     * remainder of current session </UL> <LI><B>COLUMN_NAME</B> String {@code =>} column name <LI><B>DATA_TYPE</B> int {@code =>} SQL data type from
     * java.sql.Types <LI><B>TYPE_NAME</B> String {@code =>} Data source dependent type name, for a UDT the type name is fully qualified
     * <LI><B>COLUMN_SIZE</B> int {@code =>} precision <LI><B>BUFFER_LENGTH</B> int {@code =>} not used <LI><B>DECIMAL_DIGITS</B> short  {@code =>}
     * scale - Null is returned for data types where DECIMAL_DIGITS is not applicable. <LI><B>PSEUDO_COLUMN</B> short {@code =>} is this a pseudo
     * column like an Oracle ROWID <UL> <LI> bestRowUnknown - may or may not be pseudo column <LI> bestRowNotPseudo - is NOT a pseudo column <LI>
     * bestRowPseudo - is a pseudo column </UL> </OL>
     * <p>The COLUMN_SIZE column represents the specified column size for the given column. For numeric data, this is the maximum precision.  For
     * character data, this is the length in characters. For datetime datatypes, this is the length in characters of the String representation
     * (assuming the maximum allowed precision of the fractional seconds component). For binary data, this is the length in bytes.  For the ROWID
     * datatype, this is the length in bytes. Null is returned for data types where the column size is not applicable.
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schema a schema name; must match the schema name as it is stored in the database; "" retrieves those without a schema; <code>null</code>
     * means that the schema name should not be used to narrow the search
     * @param table a table name; must match the table name as it is stored in the database
     * @param scope the scope of interest; use same values as SCOPE
     * @param nullable include columns that are nullable.
     * @return <code>ResultSet</code> - each row is a column description
     * @throws SQLException if a database access error occurs
     */
    public ResultSet getBestRowIdentifier(String catalog, String schema, String table, int scope, final boolean nullable)
            throws SQLException {

        if (table == null) {
            throw new SQLException("'table' parameter cannot be null in getBestRowIdentifier()");
        }

        String sql =
                "SELECT " + DatabaseMetaData.bestRowUnknown + " SCOPE, COLUMN_NAME,"
                        + dataTypeClause("COLUMN_TYPE") + " DATA_TYPE, DATA_TYPE TYPE_NAME,"
                        + " IF(NUMERIC_PRECISION IS NULL, CHARACTER_MAXIMUM_LENGTH, NUMERIC_PRECISION) COLUMN_SIZE, 0 BUFFER_LENGTH,"
                        + " NUMERIC_SCALE DECIMAL_DIGITS,"
                        + " 1 PSEUDO_COLUMN"
                        + " FROM INFORMATION_SCHEMA.COLUMNS"
                        + " WHERE COLUMN_KEY IN('PRI', 'MUL', 'UNI')"
                        + " AND "
                        + catalogCond("TABLE_SCHEMA", catalog)
                        + " AND TABLE_NAME = " + escapeQuote(table);

        return executeQuery(sql);
    }

    public boolean generatedKeyAlwaysReturned() throws SQLException {
        return true;
    }

    /**
     * Retrieves a description of the pseudo or hidden columns available in a given table within the specified catalog and schema. Pseudo or hidden
     * columns may not always be stored within a table and are not visible in a ResultSet unless they are specified in the query's outermost SELECT
     * list. Pseudo or hidden columns may not necessarily be able to be modified. If there are no pseudo or hidden columns, an empty ResultSet is
     * returned.
     * <P>Only column descriptions matching the catalog, schema, table and column name criteria are returned.  They are ordered by
     * <code>TABLE_CAT</code>,<code>TABLE_SCHEM</code>, <code>TABLE_NAME</code> and <code>COLUMN_NAME</code>.
     * <P>Each column description has the following columns: <OL> <LI><B>TABLE_CAT</B> String {@code =>} table catalog (may be <code>null</code>)
     * <LI><B>TABLE_SCHEM</B> String {@code =>} table schema (may be <code>null</code>) <LI><B>TABLE_NAME</B> String {@code =>} table name
     * <LI><B>COLUMN_NAME</B> String {@code =>} column name <LI><B>DATA_TYPE</B> int {@code =>} SQL type from java.sql.Types <LI><B>COLUMN_SIZE</B>
     * int {@code =>} column size. <LI><B>DECIMAL_DIGITS</B> int {@code =>} the number of fractional digits. Null is returned for data types where
     * DECIMAL_DIGITS is not applicable. <LI><B>NUM_PREC_RADIX</B> int {@code =>} Radix (typically either 10 or 2) <LI><B>COLUMN_USAGE</B> String
     * {@code =>} The allowed usage for the column.  The value returned will correspond to the enum name returned by {@link PseudoColumnUsage#name
     * PseudoColumnUsage.name()} <LI><B>REMARKS</B> String {@code =>} comment describing column (may be <code>null</code>)
     * <LI><B>CHAR_OCTET_LENGTH</B> int {@code =>} for char types the maximum number of bytes in the column <LI><B>IS_NULLABLE</B> String  {@code =>}
     * ISO rules are used to determine the nullability for a column. <UL> <LI> YES           --- if the column can include NULLs <LI> NO --- if the
     * column cannot include NULLs <LI> empty string  --- if the nullability for the column is unknown </UL> </OL>
     * <p>The COLUMN_SIZE column specifies the column size for the given column. For numeric data, this is the maximum precision.  For character data,
     * this is the length in characters. For datetime datatypes, this is the length in characters of the String representation (assuming the maximum
     * allowed precision of the fractional seconds component). For binary data, this is the length in bytes.  For the ROWID datatype, this is the
     * length in bytes. Null is returned for data types where the column size is not applicable.
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schemaPattern a schema name pattern; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param tableNamePattern a table name pattern; must match the table name as it is stored in the database
     * @param columnNamePattern a column name pattern; must match the column name as it is stored in the database
     * @return <code>ResultSet</code> - each row is a column description
     * @throws SQLException if a database access error occurs
     * @see PseudoColumnUsage
     * @since 1.7
     */
    public ResultSet getPseudoColumns(String catalog, String schemaPattern, String tableNamePattern,
                                      String columnNamePattern) throws SQLException {
        return connection.createStatement().executeQuery(
                "SELECT ' ' TABLE_CAT, ' ' TABLE_SCHEM,"
                        + "' ' TABLE_NAME, ' ' COLUMN_NAME, 0 DATA_TYPE, 0 COLUMN_SIZE, 0 DECIMAL_DIGITS,"
                        + "10 NUM_PREC_RADIX, ' ' COLUMN_USAGE,  ' ' REMARKS, 0 CHAR_OCTET_LENGTH, 'YES' IS_NULLABLE FROM DUAL "
                        + "WHERE 1=0");
    }

    public boolean allProceduresAreCallable() throws SQLException {
        return true;
    }

    public boolean allTablesAreSelectable() throws SQLException {
        return true;
    }

    @Override
    public String getURL() throws SQLException {
        return url;
    }

    public String getUserName() throws SQLException {
        return username;
    }

    public boolean isReadOnly() throws SQLException {
        return false;
    }

    public boolean nullsAreSortedHigh() throws SQLException {
        return false;
    }

    public boolean nullsAreSortedLow() throws SQLException {
        return !nullsAreSortedHigh();
    }

    public boolean nullsAreSortedAtStart() throws SQLException {
        return false;
    }

    public boolean nullsAreSortedAtEnd() throws SQLException {
        return !nullsAreSortedAtStart();
    }

    public String getDatabaseProductName() throws SQLException {
        return databaseProductName;
    }

    public String getDatabaseProductVersion() throws SQLException {
        return connection.getProtocol().getServerVersion();
    }

    public String getDriverName() throws SQLException {
        return DRIVER_NAME;
    }

    public String getDriverVersion() throws SQLException {
        return Version.version;
    }

    public int getDriverMajorVersion() {
        return Version.majorVersion;
    }

    public int getDriverMinorVersion() {
        return Version.minorVersion;
    }

    public boolean usesLocalFiles() throws SQLException {
        return false;
    }

    public boolean usesLocalFilePerTable() throws SQLException {
        return false;
    }

    public boolean supportsMixedCaseIdentifiers() throws SQLException {
        return (connection.getLowercaseTableNames() == 0);
    }

    public boolean storesUpperCaseIdentifiers() throws SQLException {
        return false;
    }

    public boolean storesLowerCaseIdentifiers() throws SQLException {
        return (connection.getLowercaseTableNames() == 1);
    }

    public boolean storesMixedCaseIdentifiers() throws SQLException {
        return (connection.getLowercaseTableNames() == 2);
    }

    public boolean supportsMixedCaseQuotedIdentifiers() throws SQLException {
        return supportsMixedCaseIdentifiers();
    }

    public boolean storesUpperCaseQuotedIdentifiers() throws SQLException {
        return storesUpperCaseIdentifiers();
    }

    public boolean storesLowerCaseQuotedIdentifiers() throws SQLException {
        return storesLowerCaseIdentifiers();
    }

    public boolean storesMixedCaseQuotedIdentifiers() throws SQLException {
        return storesMixedCaseIdentifiers();
    }

    public String getIdentifierQuoteString() throws SQLException {
        return "`";
    }

    /**
     * Retrieves a comma-separated list of all of this database's SQL keywords that are NOT also SQL:2003 keywords.
     *
     * @return the list of this database's keywords that are not also SQL:2003 keywords
     * @throws SQLException if a database access error occurs
     */
    @Override
    public String getSQLKeywords() throws SQLException {
        return "ACCESSIBLE,"
                + "ANALYZE,"
                + "ASENSITIVE,"
                + "BEFORE,"
                + "BIGINT,"
                + "BINARY,"
                + "BLOB,"
                + "CALL,"
                + "CHANGE,"
                + "CONDITION,"
                + "DATABASE,"
                + "DATABASES,"
                + "DAY_HOUR,"
                + "DAY_MICROSECOND,"
                + "DAY_MINUTE,"
                + "DAY_SECOND,"
                + "DELAYED,"
                + "DETERMINISTIC,"
                + "DISTINCTROW,"
                + "DIV,"
                + "DUAL,"
                + "EACH,"
                + "ELSEIF,"
                + "ENCLOSED,"
                + "ESCAPED,"
                + "EXIT,"
                + "EXPLAIN,"
                + "FLOAT4,"
                + "FLOAT8,"
                + "FORCE,"
                + "FULLTEXT,"
                + "HIGH_PRIORITY,"
                + "HOUR_MICROSECOND,"
                + "HOUR_MINUTE,"
                + "HOUR_SECOND,"
                + "IF,"
                + "IGNORE,"
                + "INFILE,"
                + "INOUT,"
                + "INT1,"
                + "INT2,"
                + "INT3,"
                + "INT4,"
                + "INT8,"
                + "ITERATE,"
                + "KEY,"
                + "KEYS,"
                + "KILL,"
                + "LEAVE,"
                + "LIMIT,"
                + "LINEAR,"
                + "LINES,"
                + "LOAD,"
                + "LOCALTIME,"
                + "LOCALTIMESTAMP,"
                + "LOCK,"
                + "LONG,"
                + "LONGBLOB,"
                + "LONGTEXT,"
                + "LOOP,"
                + "LOW_PRIORITY,"
                + "MEDIUMBLOB,"
                + "MEDIUMINT,"
                + "MEDIUMTEXT,"
                + "MIDDLEINT,"
                + "MINUTE_MICROSECOND,"
                + "MINUTE_SECOND,"
                + "MOD,"
                + "MODIFIES,"
                + "NO_WRITE_TO_BINLOG,"
                + "OPTIMIZE,"
                + "OPTIONALLY,"
                + "OUT,"
                + "OUTFILE,"
                + "PURGE,"
                + "RANGE,"
                + "READS,"
                + "READ_ONLY,"
                + "READ_WRITE,"
                + "REGEXP,"
                + "RELEASE,"
                + "RENAME,"
                + "REPEAT,"
                + "REPLACE,"
                + "REQUIRE,"
                + "RETURN,"
                + "RLIKE,"
                + "SCHEMAS,"
                + "SECOND_MICROSECOND,"
                + "SENSITIVE,"
                + "SEPARATOR,"
                + "SHOW,"
                + "SPATIAL,"
                + "SPECIFIC,"
                + "SQLEXCEPTION,"
                + "SQL_BIG_RESULT,"
                + "SQL_CALC_FOUND_ROWS,"
                + "SQL_SMALL_RESULT,"
                + "SSL,"
                + "STARTING,"
                + "STRAIGHT_JOIN,"
                + "TERMINATED,"
                + "TINYBLOB,"
                + "TINYINT,"
                + "TINYTEXT,"
                + "TRIGGER,"
                + "UNDO,"
                + "UNLOCK,"
                + "UNSIGNED,"
                + "USE,"
                + "UTC_DATE,"
                + "UTC_TIME,"
                + "UTC_TIMESTAMP,"
                + "VARBINARY,"
                + "VARCHARACTER,"
                + "WHILE,"
                + "X509,"
                + "XOR,"
                + "YEAR_MONTH,"
                + "ZEROFILL,"
                + "GENERAL,"
                + "IGNORE_SERVER_IDS,"
                + "MASTER_HEARTBEAT_PERIOD,"
                + "MAXVALUE,"
                + "RESIGNAL,"
                + "SIGNAL"
                + "SLOW";
    }

    public String getNumericFunctions() throws SQLException {
        return ""; //TODO : fix
    }

    public String getStringFunctions() throws SQLException {
        return ""; //TODO: fix
    }

    public String getSystemFunctions() throws SQLException {
        return "DATABASE,USER,SYSTEM_USER,SESSION_USER,LAST_INSERT_ID,VERSION";
    }

    public String getTimeDateFunctions() throws SQLException {
        return ""; //TODO : fix
    }

    public String getSearchStringEscape() throws SQLException {
        return "\\";
    }

    public String getExtraNameCharacters() throws SQLException {
        return "#@";
    }

    public boolean supportsAlterTableWithAddColumn() throws SQLException {
        return true;
    }

    public boolean supportsAlterTableWithDropColumn() throws SQLException {
        return true;
    }

    public boolean supportsColumnAliasing() throws SQLException {
        return true;
    }

    public boolean nullPlusNonNullIsNull() throws SQLException {
        return true;
    }

    public boolean supportsConvert() throws SQLException {
        return false; //TODO: fix
    }

    public boolean supportsConvert(int fromType, int toType)
            throws SQLException {
        return false; // TODO: fix
    }

    public boolean supportsTableCorrelationNames() throws SQLException {
        return true;
    }

    public boolean supportsDifferentTableCorrelationNames() throws SQLException {
        return true;
    }

    public boolean supportsExpressionsInOrderBy() throws SQLException {
        return true;
    }

    public boolean supportsOrderByUnrelated() throws SQLException {
        return false;
    }

    public boolean supportsGroupBy() throws SQLException {
        return true;
    }

    public boolean supportsGroupByUnrelated() throws SQLException {
        return true;
    }

    public boolean supportsGroupByBeyondSelect() throws SQLException {
        return true;
    }

    public boolean supportsLikeEscapeClause() throws SQLException {
        return true;
    }

    public boolean supportsMultipleResultSets() throws SQLException {
        return false;
    }

    public boolean supportsMultipleTransactions() throws SQLException {
        return true;
    }

    public boolean supportsNonNullableColumns() throws SQLException {
        return true;
    }

    @Override
    public boolean supportsMinimumSQLGrammar() throws SQLException {
        return true;
    }

    @Override
    public boolean supportsCoreSQLGrammar() throws SQLException {
        return true;
    }

    @Override
    public boolean supportsExtendedSQLGrammar() throws SQLException {
        return false;
    }

    @Override
    public boolean supportsANSI92EntryLevelSQL() throws SQLException {
        return true;
    }

    @Override
    public boolean supportsANSI92IntermediateSQL() throws SQLException {
        return false;
    }

    @Override
    public boolean supportsANSI92FullSQL() throws SQLException {
        return false;
    }

    public boolean supportsIntegrityEnhancementFacility() throws SQLException {
        return false; //TODO: verify
    }

    public boolean supportsOuterJoins() throws SQLException {
        return true;
    }

    public boolean supportsFullOuterJoins() throws SQLException {
        return false;
    }

    public boolean supportsLimitedOuterJoins() throws SQLException {
        return true;
    }

    public String getSchemaTerm() throws SQLException {
        return "";
    }

    public String getProcedureTerm() throws SQLException {
        return "procedure";
    }

    public String getCatalogTerm() throws SQLException {
        return "database";
    }

    public boolean isCatalogAtStart() throws SQLException {
        return true;
    }

    public String getCatalogSeparator() throws SQLException {
        return ".";
    }

    public boolean supportsSchemasInDataManipulation() throws SQLException {
        return false;
    }

    public boolean supportsSchemasInProcedureCalls() throws SQLException {
        return false;
    }

    public boolean supportsSchemasInTableDefinitions() throws SQLException {
        return false;
    }

    public boolean supportsSchemasInIndexDefinitions() throws SQLException {
        return false;
    }

    public boolean supportsSchemasInPrivilegeDefinitions() throws SQLException {
        return true;
    }

    public boolean supportsCatalogsInDataManipulation() throws SQLException {
        return true;
    }

    public boolean supportsCatalogsInProcedureCalls() throws SQLException {
        return true;
    }

    public boolean supportsCatalogsInTableDefinitions() throws SQLException {
        return true;
    }

    public boolean supportsCatalogsInIndexDefinitions() throws SQLException {
        return true;
    }

    public boolean supportsCatalogsInPrivilegeDefinitions() throws SQLException {
        return true;
    }

    public boolean supportsPositionedDelete() throws SQLException {
        return false;
    }

    public boolean supportsPositionedUpdate() throws SQLException {
        return false;
    }

    public boolean supportsSelectForUpdate() throws SQLException {
        return true;
    }

    public boolean supportsStoredProcedures() throws SQLException {
        return true;
    }

    public boolean supportsSubqueriesInComparisons() throws SQLException {
        return true;
    }

    public boolean supportsSubqueriesInExists() throws SQLException {
        return true;
    }

    public boolean supportsSubqueriesInIns() throws SQLException {
        return true;
    }

    public boolean supportsSubqueriesInQuantifieds() throws SQLException {
        return true;
    }

    public boolean supportsCorrelatedSubqueries() throws SQLException {
        return true;
    }

    public boolean supportsUnion() throws SQLException {
        return true;
    }

    public boolean supportsUnionAll() throws SQLException {
        return true;
    }

    public boolean supportsOpenCursorsAcrossCommit() throws SQLException {
        return true;
    }

    public boolean supportsOpenCursorsAcrossRollback() throws SQLException {
        return true;
    }

    public boolean supportsOpenStatementsAcrossCommit() throws SQLException {
        return true;
    }

    public boolean supportsOpenStatementsAcrossRollback() throws SQLException {
        return true;
    }

    public int getMaxBinaryLiteralLength() throws SQLException {
        return 16777208;
    }

    public int getMaxCharLiteralLength() throws SQLException {
        return 16777208;
    }

    public int getMaxColumnNameLength() throws SQLException {
        return 64;
    }

    public int getMaxColumnsInGroupBy() throws SQLException {
        return 64;
    }

    public int getMaxColumnsInIndex() throws SQLException {
        return 16;
    }

    public int getMaxColumnsInOrderBy() throws SQLException {
        return 64;
    }

    public int getMaxColumnsInSelect() throws SQLException {
        return 256;
    }

    public int getMaxColumnsInTable() throws SQLException {
        return 0;
    }

    public int getMaxConnections() throws SQLException {
        return 0;
    }

    public int getMaxCursorNameLength() throws SQLException {
        return 0;
    }

    public int getMaxIndexLength() throws SQLException {
        return 256;
    }

    public int getMaxSchemaNameLength() throws SQLException {
        return 32;
    }

    public int getMaxProcedureNameLength() throws SQLException {
        return 256;
    }

    public int getMaxCatalogNameLength() throws SQLException {
        return 0;
    }

    public int getMaxRowSize() throws SQLException {
        return 0;
    }

    public boolean doesMaxRowSizeIncludeBlobs() throws SQLException {
        return false;
    }

    public int getMaxStatementLength() throws SQLException {
        return 0;
    }

    public int getMaxStatements() throws SQLException {
        return 0;
    }

    public int getMaxTableNameLength() throws SQLException {
        return 64;
    }

    public int getMaxTablesInSelect() throws SQLException {
        return 256;
    }

    public int getMaxUserNameLength() throws SQLException {
        return 16;
    }

    public int getDefaultTransactionIsolation() throws SQLException {
        return Connection.TRANSACTION_REPEATABLE_READ;
    }

    /**
     * Retrieves whether this database supports transactions. If not, invoking the method <code>commit</code> is a noop, and the isolation level is
     * <code>TRANSACTION_NONE</code>.
     *
     * @return <code>true</code> if transactions are supported; <code>false</code> otherwise
     * @throws SQLException if a database access error occurs
     */
    public boolean supportsTransactions() throws SQLException {
        return true;
    }


    /* Helper to generate  information schema with "equality" condition (typically on catalog name)
     */

    /**
     * Retrieves whether this database supports the given transaction isolation level.
     *
     * @param level one of the transaction isolation levels defined in <code>java.sql.Connection</code>
     * @return <code>true</code> if so; <code>false</code> otherwise
     * @throws SQLException if a database access error occurs
     * @see Connection
     */
    public boolean supportsTransactionIsolationLevel(int level) throws SQLException {
        switch (level) {
            case Connection.TRANSACTION_READ_UNCOMMITTED:
            case Connection.TRANSACTION_READ_COMMITTED:
            case Connection.TRANSACTION_REPEATABLE_READ:
            case Connection.TRANSACTION_SERIALIZABLE:
                return true;
            default:
                return false;
        }
    }

    public boolean supportsDataDefinitionAndDataManipulationTransactions() throws SQLException {
        return true;
    }

    public boolean supportsDataManipulationTransactionsOnly() throws SQLException {
        return false;
    }

    public boolean dataDefinitionCausesTransactionCommit() throws SQLException {
        return true;
    }

    public boolean dataDefinitionIgnoredInTransactions() throws SQLException {
        return false;
    }

    /**
     * Retrieves a description of the stored procedures available in the given catalog.
     * Only procedure descriptions matching the schema and procedure name criteria are returned.  They are ordered by <code>PROCEDURE_CAT</code>,
     * <code>PROCEDURE_SCHEM</code>, <code>PROCEDURE_NAME</code> and <code>SPECIFIC_ NAME</code>.
     * <P>Each procedure description has the the following columns: <OL> <LI><B>PROCEDURE_CAT</B> String {@code =>} procedure catalog (may be
     * <code>null</code>) <LI><B>PROCEDURE_SCHEM</B> String {@code =>} procedure schema (may be <code>null</code>) <LI><B>PROCEDURE_NAME</B> String
     * {@code =>} procedure name <LI> reserved for future use <LI> reserved for future use <LI> reserved for future use <LI><B>REMARKS</B> String
     * {@code =>} explanatory comment on the procedure <LI><B>PROCEDURE_TYPE</B> short {@code =>} kind of procedure: <UL> <LI> procedureResultUnknown
     * - Cannot determine if  a return value will be returned <LI> procedureNoResult - Does not return a return value <LI> procedureReturnsResult -
     * Returns a return value </UL> <LI><B>SPECIFIC_NAME</B> String  {@code =>} The name which uniquely identifies this procedure within its schema.
     * </OL>
     * A user may not have permissions to execute any of the procedures that are returned by <code>getProcedures</code>
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schemaPattern a schema name pattern; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param procedureNamePattern a procedure name pattern; must match the procedure name as it is stored in the database
     * @return <code>ResultSet</code> - each row is a procedure description
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     */
    public ResultSet getProcedures(String catalog, String schemaPattern, String procedureNamePattern)
            throws SQLException {

        String sql =
                "SELECT ROUTINE_SCHEMA PROCEDURE_CAT,NULL PROCEDURE_SCHEM, ROUTINE_NAME PROCEDURE_NAME,"
                        + " NULL RESERVED1, NULL RESERVED2, NULL RESERVED3,"
                        + " CASE ROUTINE_TYPE "
                        + "  WHEN 'FUNCTION' THEN " + procedureReturnsResult
                        + "  WHEN 'PROCEDURE' THEN " + procedureNoResult
                        + "  ELSE " + procedureResultUnknown
                        + " END PROCEDURE_TYPE,"
                        + " ROUTINE_COMMENT REMARKS, SPECIFIC_NAME "
                        + " FROM INFORMATION_SCHEMA.ROUTINES "
                        + " WHERE "
                        + catalogCond("ROUTINE_SCHEMA", catalog)
                        + " AND "
                        + patternCond("ROUTINE_NAME", procedureNamePattern)
                        + "/* AND ROUTINE_TYPE='PROCEDURE' */";
        return executeQuery(sql);
    }

    /* Is INFORMATION_SCHEMA.PARAMETERS available ?*/
    boolean haveInformationSchemaParameters() {
        return connection.getProtocol().versionGreaterOrEqual(5, 5, 3);
    }

    /**
     * Retrieves a description of the given catalog's stored procedure parameter and result columns.
     * <P>Only descriptions matching the schema, procedure and parameter name criteria are returned.  They are ordered by PROCEDURE_CAT,
     * PROCEDURE_SCHEM, PROCEDURE_NAME and SPECIFIC_NAME. Within this, the return value, if any, is first. Next are the parameter descriptions in call
     * order. The column descriptions follow in column number order.
     * <P>Each row in the <code>ResultSet</code> is a parameter description or column description with the following fields: <OL>
     * <LI><B>PROCEDURE_CAT</B> String {@code =>} procedure catalog (may be <code>null</code>) <LI><B>PROCEDURE_SCHEM</B> String {@code =>} procedure
     * schema (may be <code>null</code>) <LI><B>PROCEDURE_NAME</B> String {@code =>} procedure name <LI><B>COLUMN_NAME</B> String {@code =>}
     * column/parameter name <LI><B>COLUMN_TYPE</B> Short {@code =>} kind of column/parameter: <UL> <LI> procedureColumnUnknown - nobody knows <LI>
     * procedureColumnIn - IN parameter <LI> procedureColumnInOut - INOUT parameter <LI> procedureColumnOut - OUT parameter <LI> procedureColumnReturn
     * - procedure return value <LI> procedureColumnResult - result column in <code>ResultSet</code> </UL> <LI><B>DATA_TYPE</B> int {@code =>} SQL
     * type from java.sql.Types <LI><B>TYPE_NAME</B> String {@code =>} SQL type name, for a UDT type the type name is fully qualified
     * <LI><B>PRECISION</B> int {@code =>} precision <LI><B>LENGTH</B> int {@code =>} length in bytes of data <LI><B>SCALE</B> short {@code =>} scale
     * -  null is returned for data types where SCALE is not applicable. <LI><B>RADIX</B> short {@code =>} radix <LI><B>NULLABLE</B> short {@code =>}
     * can it contain NULL. <UL> <LI> procedureNoNulls - does not allow NULL values <LI> procedureNullable - allows NULL values <LI>
     * procedureNullableUnknown - nullability unknown </UL> <LI><B>REMARKS</B> String {@code =>} comment describing parameter/column
     * <LI><B>COLUMN_DEF</B> String {@code =>} default value for the column, which should be interpreted as a string when the value is enclosed in
     * single quotes (may be <code>null</code>) <UL> <LI> The string NULL (not enclosed in quotes) - if NULL was specified as the default value <LI>
     * TRUNCATE (not enclosed in quotes)        - if the specified default value cannot be represented without truncation <LI> NULL - if a default
     * value was not specified </UL> <LI><B>SQL_DATA_TYPE</B> int  {@code =>} reserved for future use <LI><B>SQL_DATETIME_SUB</B> int  {@code =>}
     * reserved for future use <LI><B>CHAR_OCTET_LENGTH</B> int  {@code =>} the maximum length of binary and character based columns.  For any other
     * datatype the returned value is a NULL <LI><B>ORDINAL_POSITION</B> int  {@code =>} the ordinal position, starting from 1, for the input and
     * output parameters for a procedure. A value of 0 is returned if this row describes the procedure's return value.  For result set columns, it is
     * the ordinal position of the column in the result set starting from 1.  If there are multiple result sets, the column ordinal positions are
     * implementation defined. <LI><B>IS_NULLABLE</B> String  {@code =>} ISO rules are used to determine the nullability for a column. <UL> <LI> YES
     * --- if the column can include NULLs <LI> NO            --- if the column cannot include NULLs <LI> empty string  --- if the nullability for the
     * column is unknown </UL> <LI><B>SPECIFIC_NAME</B> String  {@code =>} the name which uniquely identifies this procedure within its schema. </OL>
     * <P><B>Note:</B> Some databases may not return the column descriptions for a procedure.
     * <p>The PRECISION column represents the specified column size for the given column. For numeric data, this is the maximum precision.  For
     * character data, this is the length in characters. For datetime datatypes, this is the length in characters of the String representation
     * (assuming the maximum allowed precision of the fractional seconds component). For binary data, this is the length in bytes.  For the ROWID
     * datatype, this is the length in bytes. Null is returned for data types where the column size is not applicable.
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schemaPattern a schema name pattern; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param procedureNamePattern a procedure name pattern; must match the procedure name as it is stored in the database
     * @param columnNamePattern a column name pattern; must match the column name as it is stored in the database
     * @return <code>ResultSet</code> - each row describes a stored procedure parameter or column
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     */
    public ResultSet getProcedureColumns(String catalog, String schemaPattern, String procedureNamePattern,
                                         String columnNamePattern) throws SQLException {
        String sql;

        if (haveInformationSchemaParameters()) {
            /*
             *  Get info from information_schema.parameters
             */
            sql = "SELECT SPECIFIC_SCHEMA PROCEDURE_CAT, NULL PROCEDURE_SCHEM, SPECIFIC_NAME PROCEDURE_NAME,"
                    + " PARAMETER_NAME COLUMN_NAME, "
                    + " CASE PARAMETER_MODE "
                    + "  WHEN 'IN' THEN " + procedureColumnIn
                    + "  WHEN 'OUT' THEN " + procedureColumnOut
                    + "  WHEN 'INOUT' THEN " + procedureColumnInOut
                    + "  ELSE IF(PARAMETER_MODE IS NULL," + procedureColumnReturn + "," + procedureColumnUnknown + ")"
                    + " END COLUMN_TYPE,"
                    + dataTypeClause("DTD_IDENTIFIER") + " DATA_TYPE,"
                    + "DATA_TYPE TYPE_NAME,"
                    + " CASE DATA_TYPE"
                    + "  WHEN 'time' THEN "
                        + (datePrecisionColumnExist ? "IF(DATETIME_PRECISION = 0, 10, CAST(11 + DATETIME_PRECISION as signed integer))" : "10")
                    + "  WHEN 'date' THEN 10"
                    + "  WHEN 'datetime' THEN "
                        + (datePrecisionColumnExist ? "IF(DATETIME_PRECISION = 0, 19, CAST(20 + DATETIME_PRECISION as signed integer))" : "19")
                    + "  WHEN 'timestamp' THEN "
                        + (datePrecisionColumnExist ? "IF(DATETIME_PRECISION = 0, 19, CAST(20 + DATETIME_PRECISION as signed integer))" : "19")
                    + "  ELSE "
                    + "  IF(NUMERIC_PRECISION IS NULL, LEAST(CHARACTER_MAXIMUM_LENGTH," + Integer.MAX_VALUE + "), NUMERIC_PRECISION) "
                    + " END `PRECISION`,"

                    + " CASE DATA_TYPE"
                    + "  WHEN 'time' THEN "
                        + (datePrecisionColumnExist ? "IF(DATETIME_PRECISION = 0, 10, CAST(11 + DATETIME_PRECISION as signed integer))" : "10")
                    + "  WHEN 'date' THEN 10"
                    + "  WHEN 'datetime' THEN "
                        + (datePrecisionColumnExist ? "IF(DATETIME_PRECISION = 0, 19, CAST(20 + DATETIME_PRECISION as signed integer))" : "19")
                    + "  WHEN 'timestamp' THEN "
                        + (datePrecisionColumnExist ? "IF(DATETIME_PRECISION = 0, 19, CAST(20 + DATETIME_PRECISION as signed integer))" : "19")
                    + "  ELSE "
                    + "  IF(NUMERIC_PRECISION IS NULL, LEAST(CHARACTER_MAXIMUM_LENGTH," + Integer.MAX_VALUE + "), NUMERIC_PRECISION) "
                    + " END `LENGTH`,"

                    + (datePrecisionColumnExist ? " CASE DATA_TYPE"
                    + "  WHEN 'time' THEN CAST(DATETIME_PRECISION as signed integer)"
                    + "  WHEN 'datetime' THEN CAST(DATETIME_PRECISION as signed integer)"
                    + "  WHEN 'timestamp' THEN CAST(DATETIME_PRECISION as signed integer)"
                    + "  ELSE NUMERIC_SCALE "
                    + " END `SCALE`," : " NUMERIC_SCALE `SCALE`,")

                    + "10 RADIX,"
                    + procedureNullableUnknown + " NULLABLE,NULL REMARKS,NULL COLUMN_DEF,0 SQL_DATA_TYPE,0 SQL_DATETIME_SUB,"
                    + "CHARACTER_OCTET_LENGTH CHAR_OCTET_LENGTH ,ORDINAL_POSITION, '' IS_NULLABLE, SPECIFIC_NAME "
                    + " FROM INFORMATION_SCHEMA.PARAMETERS "
                    + " WHERE "
                    + catalogCond("SPECIFIC_SCHEMA", catalog)
                    + " AND " + patternCond("SPECIFIC_NAME", procedureNamePattern)
                    + " AND " + patternCond("PARAMETER_NAME", columnNamePattern)
                    + " /* AND ROUTINE_TYPE='PROCEDURE' */ "
                    + " ORDER BY SPECIFIC_SCHEMA, SPECIFIC_NAME, ORDINAL_POSITION";
        } else {

            /* No information_schema.parameters
             * TODO : figure out what to do with older versions (get info via mysql.proc)
             * For now, just a dummy result set is returned.
             */
            sql =
                    "SELECT '' PROCEDURE_CAT, '' PROCEDURE_SCHEM , '' PROCEDURE_NAME,'' COLUMN_NAME, 0 COLUMN_TYPE,"
                            + "0 DATA_TYPE,'' TYPE_NAME, 0 `PRECISION`,0 LENGTH, 0 SCALE,10 RADIX,"
                            + "0 NULLABLE,NULL REMARKS,NULL COLUMN_DEF,0 SQL_DATA_TYPE,0 SQL_DATETIME_SUB,"
                            + "0 CHAR_OCTET_LENGTH ,0 ORDINAL_POSITION, '' IS_NULLABLE, '' SPECIFIC_NAME "
                            + " FROM DUAL "
                            + " WHERE 1=0 ";
        }

        try {
            return executeQuery(sql);
        } catch (SQLException sqlException) {
            if (sqlException.getMessage().contains("Unknown column 'DATETIME_PRECISION'")) {
                datePrecisionColumnExist = false;
                return getProcedureColumns(catalog, schemaPattern, procedureNamePattern, columnNamePattern);
            }
            throw sqlException;
        }
    }

    /**
     * Retrieves a description of the given catalog's system or user function parameters and return type.
     * <P>Only descriptions matching the schema,  function and parameter name criteria are returned. They are ordered by <code>FUNCTION_CAT</code>,
     * <code>FUNCTION_SCHEM</code>, <code>FUNCTION_NAME</code> and <code>SPECIFIC_ NAME</code>. Within this, the return value, if any, is first. Next
     * are the parameter descriptions in call order. The column descriptions follow in column number order.
     * <P>Each row in the <code>ResultSet</code> is a parameter description, column description or return type description with the following fields:
     * <OL> <LI><B>FUNCTION_CAT</B> String {@code =>} function catalog (may be <code>null</code>) <LI><B>FUNCTION_SCHEM</B> String {@code =>} function
     * schema (may be <code>null</code>) <LI><B>FUNCTION_NAME</B> String {@code =>} function name.  This is the name used to invoke the function
     * <LI><B>COLUMN_NAME</B> String {@code =>} column/parameter name <LI><B>COLUMN_TYPE</B> Short {@code =>} kind of column/parameter: <UL> <LI>
     * functionColumnUnknown - nobody knows <LI> functionColumnIn - IN parameter <LI> functionColumnInOut - INOUT parameter <LI> functionColumnOut -
     * OUT parameter <LI> functionColumnReturn - function return value <LI> functionColumnResult - Indicates that the parameter or column is a column
     * in the <code>ResultSet</code> </UL> <LI><B>DATA_TYPE</B> int {@code =>} SQL type from java.sql.Types <LI><B>TYPE_NAME</B> String {@code =>} SQL
     * type name, for a UDT type the type name is fully qualified <LI><B>PRECISION</B> int {@code =>} precision <LI><B>LENGTH</B> int {@code =>}
     * length in bytes of data <LI><B>SCALE</B> short {@code =>} scale -  null is returned for data types where SCALE is not applicable.
     * <LI><B>RADIX</B> short {@code =>} radix <LI><B>NULLABLE</B> short {@code =>} can it contain NULL. <UL> <LI> functionNoNulls - does not allow
     * NULL values <LI> functionNullable - allows NULL values <LI> functionNullableUnknown - nullability unknown </UL> <LI><B>REMARKS</B> String
     * {@code =>} comment describing column/parameter <LI><B>CHAR_OCTET_LENGTH</B> int  {@code =>} the maximum length of binary and character based
     * parameters or columns.  For any other datatype the returned value is a NULL <LI><B>ORDINAL_POSITION</B> int  {@code =>} the ordinal position,
     * starting from 1, for the input and output parameters. A value of 0 is returned if this row describes the function's return value. For result
     * set columns, it is the ordinal position of the column in the result set starting from 1. <LI><B>IS_NULLABLE</B> String  {@code =>} ISO rules
     * are used to determine the nullability for a parameter or column. <UL> <LI> YES           --- if the parameter or column can include NULLs <LI>
     * NO            --- if the parameter or column  cannot include NULLs <LI> empty string  --- if the nullability for the parameter  or column is
     * unknown </UL> <LI><B>SPECIFIC_NAME</B> String  {@code =>} the name which uniquely identifies this function within its schema.  This is a user
     * specified, or DBMS generated, name that may be different then the <code>FUNCTION_NAME</code> for example with overload functions </OL>
     * <p>The PRECISION column represents the specified column size for the given parameter or column. For numeric data, this is the maximum
     * precision.  For character data, this is the length in characters. For datetime datatypes, this is the length in characters of the String
     * representation (assuming the maximum allowed precision of the fractional seconds component). For binary data, this is the length in bytes.  For
     * the ROWID datatype, this is the length in bytes. Null is returned for data types where the column size is not applicable.
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schemaPattern a schema name pattern; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param functionNamePattern a procedure name pattern; must match the function name as it is stored in the database
     * @param columnNamePattern a parameter name pattern; must match the parameter or column name as it is stored in the database
     * @return <code>ResultSet</code> - each row describes a user function parameter, column  or return type
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     * @since 1.6
     */
    public ResultSet getFunctionColumns(String catalog, String schemaPattern, String functionNamePattern,
                                        String columnNamePattern) throws SQLException {

        String sql;
        if (haveInformationSchemaParameters()) {

            sql = "SELECT SPECIFIC_SCHEMA `FUNCTION_CAT`, NULL `FUNCTION_SCHEM`, SPECIFIC_NAME FUNCTION_NAME,"
                    + " PARAMETER_NAME COLUMN_NAME, "
                    + " CASE PARAMETER_MODE "
                    + "  WHEN 'IN' THEN " + functionColumnIn
                    + "  WHEN 'OUT' THEN " + functionColumnOut
                    + "  WHEN 'INOUT' THEN " + functionColumnInOut
                    + "  ELSE " + functionReturn
                    + " END COLUMN_TYPE,"
                    + dataTypeClause("DTD_IDENTIFIER") + " DATA_TYPE,"
                    + "DATA_TYPE TYPE_NAME,NUMERIC_PRECISION `PRECISION`,CHARACTER_MAXIMUM_LENGTH LENGTH,NUMERIC_SCALE SCALE,10 RADIX,"
                    + procedureNullableUnknown + " NULLABLE,NULL REMARKS,"
                    + "CHARACTER_OCTET_LENGTH CHAR_OCTET_LENGTH ,ORDINAL_POSITION, '' IS_NULLABLE, SPECIFIC_NAME "
                    + " FROM INFORMATION_SCHEMA.PARAMETERS "
                    + " WHERE "
                    + catalogCond("SPECIFIC_SCHEMA", catalog)
                    + " AND " + patternCond("SPECIFIC_NAME", functionNamePattern)
                    + " AND " + patternCond("PARAMETER_NAME", columnNamePattern)
                    + " AND ROUTINE_TYPE='FUNCTION'"
                    + " ORDER BY FUNCTION_CAT, SPECIFIC_NAME, ORDINAL_POSITION";
        } else {
            /*
             * No information_schema.parameters
             * TODO : figure out what to do with older versions (get info via mysql.proc)
             * For now, just a dummy result set is returned.
             */
            sql =
                    "SELECT '' FUNCTION_CAT, NULL FUNCTION_SCHEM, '' FUNCTION_NAME,"
                            + " '' COLUMN_NAME, 0  COLUMN_TYPE, 0 DATA_TYPE,"
                            + " '' TYPE_NAME,0 `PRECISION`,0 LENGTH, 0 SCALE,0 RADIX,"
                            + " 0 NULLABLE,NULL REMARKS, 0 CHAR_OCTET_LENGTH , 0 ORDINAL_POSITION, "
                            + " '' IS_NULLABLE, '' SPECIFIC_NAME "
                            + " FROM DUAL WHERE 1=0 ";
        }
        return executeQuery(sql);
    }

    public ResultSet getSchemas() throws SQLException {
        return executeQuery(
                "SELECT '' TABLE_SCHEM, '' TABLE_catalog  FROM DUAL WHERE 1=0");
    }

    public ResultSet getSchemas(String catalog, String schemaPattern) throws SQLException {
        return executeQuery("SELECT  ' ' table_schem, ' ' table_catalog FROM DUAL WHERE 1=0");
    }

    public ResultSet getCatalogs() throws SQLException {
        return executeQuery(
                "SELECT SCHEMA_NAME TABLE_CAT FROM INFORMATION_SCHEMA.SCHEMATA ORDER BY 1");
    }

    public ResultSet getTableTypes() throws SQLException {
        return executeQuery(
                "SELECT 'TABLE' TABLE_TYPE UNION SELECT 'SYSTEM VIEW' TABLE_TYPE UNION SELECT 'VIEW' TABLE_TYPE");
    }

    /**
     * Retrieves a description of the access rights for a table's columns.
     * <P>Only privileges matching the column name criteria are returned.  They are ordered by COLUMN_NAME and PRIVILEGE.
     * <P>Each privilege description has the following columns: <OL> <LI><B>TABLE_CAT</B> String {@code =>} table catalog (may be <code>null</code>)
     * <LI><B>TABLE_SCHEM</B> String {@code =>} table schema (may be <code>null</code>) <LI><B>TABLE_NAME</B> String {@code =>} table name
     * <LI><B>COLUMN_NAME</B> String {@code =>} column name <LI><B>GRANTOR</B> String {@code =>} grantor of access (may be <code>null</code>)
     * <LI><B>GRANTEE</B> String {@code =>} grantee of access <LI><B>PRIVILEGE</B> String {@code =>} name of access (SELECT, INSERT, UPDATE,
     * REFRENCES, ...) <LI><B>IS_GRANTABLE</B> String {@code =>} "YES" if grantee is permitted to grant to others; "NO" if not; <code>null</code> if
     * unknown </OL>
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schema a schema name; must match the schema name as it is stored in the database; "" retrieves those without a schema; <code>null</code>
     * means that the schema name should not be used to narrow the search
     * @param table a table name; must match the table name as it is stored in the database
     * @param columnNamePattern a column name pattern; must match the column name as it is stored in the database
     * @return <code>ResultSet</code> - each row is a column privilege description
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     */
    public ResultSet getColumnPrivileges(String catalog, String schema, String table,
                                         String columnNamePattern) throws SQLException {

        if (table == null) {
            throw new SQLException("'table' parameter must not be null");
        }
        String sql =
                "SELECT TABLE_SCHEMA TABLE_CAT, NULL TABLE_SCHEM, TABLE_NAME,"
                        + " COLUMN_NAME, NULL AS GRANTOR, GRANTEE, PRIVILEGE_TYPE AS PRIVILEGE, IS_GRANTABLE FROM "
                        + " INFORMATION_SCHEMA.COLUMN_PRIVILEGES WHERE "
                        + catalogCond("TABLE_SCHEMA", catalog)
                        + " AND "
                        + " TABLE_NAME = " + escapeQuote(table)
                        + " AND "
                        + patternCond("COLUMN_NAME", columnNamePattern)
                        + " ORDER BY COLUMN_NAME, PRIVILEGE_TYPE";

        return executeQuery(sql);
    }

    /**
     * Retrieves a description of the access rights for each table available in a catalog. Note that a table privilege applies to one or more columns
     * in the table. It would be wrong to assume that this privilege applies to all columns (this may be true for some systems but is not true for
     * all.)
     * <P>Only privileges matching the schema and table name criteria are returned.  They are ordered by <code>TABLE_CAT</code>,
     * <code>TABLE_SCHEM</code>, <code>TABLE_NAME</code>, and <code>PRIVILEGE</code>.
     * <P>Each privilege description has the following columns: <OL> <LI><B>TABLE_CAT</B> String {@code =>} table catalog (may be <code>null</code>)
     * <LI><B>TABLE_SCHEM</B> String {@code =>} table schema (may be <code>null</code>) <LI><B>TABLE_NAME</B> String {@code =>} table name
     * <LI><B>GRANTOR</B> String {@code =>} grantor of access (may be <code>null</code>) <LI><B>GRANTEE</B> String {@code =>} grantee of access
     * <LI><B>PRIVILEGE</B> String {@code =>} name of access (SELECT, INSERT, UPDATE, REFRENCES, ...) <LI><B>IS_GRANTABLE</B> String {@code =>} "YES"
     * if grantee is permitted to grant to others; "NO" if not; <code>null</code> if unknown </OL>
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schemaPattern a schema name pattern; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param tableNamePattern a table name pattern; must match the table name as it is stored in the database
     * @return <code>ResultSet</code> - each row is a table privilege description
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     */
    public ResultSet getTablePrivileges(String catalog, String schemaPattern, String tableNamePattern)
            throws SQLException {
        String sql =
                "SELECT TABLE_SCHEMA TABLE_CAT,NULL  TABLE_SCHEM, TABLE_NAME, NULL GRANTOR,"
                        + "GRANTEE, PRIVILEGE_TYPE  PRIVILEGE, IS_GRANTABLE  FROM INFORMATION_SCHEMA.TABLE_PRIVILEGES "
                        + " WHERE "
                        + catalogCond("TABLE_SCHEMA", catalog)
                        + " AND "
                        + patternCond("TABLE_NAME", tableNamePattern)
                        + "ORDER BY TABLE_SCHEMA, TABLE_NAME,  PRIVILEGE_TYPE ";

        return executeQuery(sql);
    }

    /**
     * Retrieves a description of a table's columns that are automatically updated when any value in a row is updated.  They are unordered.
     * <P>Each column description has the following columns: <OL> <LI><B>SCOPE</B> short {@code =>} is not used <LI><B>COLUMN_NAME</B> String {@code
     * =>} column name <LI><B>DATA_TYPE</B> int {@code =>} SQL data type from <code>java.sql.Types</code> <LI><B>TYPE_NAME</B> String {@code =>} Data
     * source-dependent type name <LI><B>COLUMN_SIZE</B> int {@code =>} precision <LI><B>BUFFER_LENGTH</B> int {@code =>} length of column value in
     * bytes <LI><B>DECIMAL_DIGITS</B> short  {@code =>} scale - Null is returned for data types where DECIMAL_DIGITS is not applicable.
     * <LI><B>PSEUDO_COLUMN</B> short {@code =>} whether this is pseudo column like an Oracle ROWID <UL> <LI> versionColumnUnknown - may or may not be
     * pseudo column <LI> versionColumnNotPseudo - is NOT a pseudo column <LI> versionColumnPseudo - is a pseudo column </UL> </OL>
     * <p>The COLUMN_SIZE column represents the specified column size for the given column. For numeric data, this is the maximum precision.  For
     * character data, this is the length in characters. For datetime datatypes, this is the length in characters of the String representation
     * (assuming the maximum allowed precision of the fractional seconds component). For binary data, this is the length in bytes.  For the ROWID
     * datatype, this is the length in bytes. Null is returned for data types where the column size is not applicable.
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schema a schema name; must match the schema name as it is stored in the database; "" retrieves those without a schema; <code>null</code>
     * means that the schema name should not be used to narrow the search
     * @param table a table name; must match the table name as it is stored in the database
     * @return a <code>ResultSet</code> object in which each row is a column description
     * @throws SQLException if a database access error occurs
     */
    public ResultSet getVersionColumns(String catalog, String schema, String table)
            throws SQLException {
        String sql =
                "SELECT 0 SCOPE, ' ' COLUMN_NAME, 0 DATA_TYPE,"
                        + " ' ' TYPE_NAME, 0 COLUMN_SIZE, 0 BUFFER_LENGTH,"
                        + " 0 DECIMAL_DIGITS, 0 PSEUDO_COLUMN "
                        + " FROM DUAL WHERE 1 = 0";
        return executeQuery(sql);
    }

    /**
     * Retrieves a description of the foreign key columns in the given foreign key table that reference the primary key or the columns representing a
     * unique constraint of the  parent table (could be the same or a different table). The number of columns returned from the parent table must
     * match the number of columns that make up the foreign key.  They are ordered by FKTABLE_CAT, FKTABLE_SCHEM, FKTABLE_NAME, and KEY_SEQ.
     * <P>Each foreign key column description has the following columns: <OL> <LI><B>PKTABLE_CAT</B> String {@code =>} parent key table catalog (may
     * be <code>null</code>) <LI><B>PKTABLE_SCHEM</B> String {@code =>} parent key table schema (may be <code>null</code>) <LI><B>PKTABLE_NAME</B>
     * String {@code =>} parent key table name <LI><B>PKCOLUMN_NAME</B> String {@code =>} parent key column name <LI><B>FKTABLE_CAT</B> String {@code
     * =>} foreign key table catalog (may be <code>null</code>) being exported (may be <code>null</code>) <LI><B>FKTABLE_SCHEM</B> String {@code =>}
     * foreign key table schema (may be <code>null</code>) being exported (may be <code>null</code>) <LI><B>FKTABLE_NAME</B> String {@code =>} foreign
     * key table name being exported <LI><B>FKCOLUMN_NAME</B> String {@code =>} foreign key column name being exported <LI><B>KEY_SEQ</B> short {@code
     * =>} sequence number within foreign key( a value of 1 represents the first column of the foreign key, a value of 2 would represent the second
     * column within the foreign key). <LI><B>UPDATE_RULE</B> short {@code =>} What happens to foreign key when parent key is updated: <UL> <LI>
     * importedNoAction - do not allow update of parent key if it has been imported <LI> importedKeyCascade - change imported key to agree with parent
     * key update <LI> importedKeySetNull - change imported key to <code>NULL</code> if its parent key has been updated <LI> importedKeySetDefault -
     * change imported key to default values if its parent key has been updated <LI> importedKeyRestrict - same as importedKeyNoAction (for ODBC 2.x
     * compatibility) </UL> <LI><B>DELETE_RULE</B> short {@code =>} What happens to the foreign key when parent key is deleted. <UL> <LI>
     * importedKeyNoAction - do not allow delete of parent key if it has been imported <LI> importedKeyCascade - delete rows that import a deleted key
     * <LI> importedKeySetNull - change imported key to <code>NULL</code> if its primary key has been deleted <LI> importedKeyRestrict - same as
     * importedKeyNoAction (for ODBC 2.x compatibility) <LI> importedKeySetDefault - change imported key to default if its parent key has been deleted
     * </UL> <LI><B>FK_NAME</B> String {@code =>} foreign key name (may be <code>null</code>) <LI><B>PK_NAME</B> String {@code =>} parent key name
     * (may be <code>null</code>) <LI><B>DEFERRABILITY</B> short {@code =>} can the evaluation of foreign key constraints be deferred until commit
     * <UL> <LI> importedKeyInitiallyDeferred - see SQL92 for definition <LI> importedKeyInitiallyImmediate - see SQL92 for definition <LI>
     * importedKeyNotDeferrable - see SQL92 for definition </UL> </OL>
     *
     * @param parentCatalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means drop catalog name from the selection criteria
     * @param parentSchema a schema name; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means drop schema name from the selection criteria
     * @param parentTable the name of the table that exports the key; must match the table name as it is stored in the database
     * @param foreignCatalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means drop catalog name from the selection criteria
     * @param foreignSchema a schema name; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means drop schema name from the selection criteria
     * @param foreignTable the name of the table that imports the key; must match the table name as it is stored in the database
     * @return <code>ResultSet</code> - each row is a foreign key column description
     * @throws SQLException if a database access error occurs
     * @see #getImportedKeys
     */
    public ResultSet getCrossReference(String parentCatalog, String parentSchema, String parentTable,
                                       String foreignCatalog, String foreignSchema, String foreignTable)
            throws SQLException {

        String sql =
                "SELECT KCU.REFERENCED_TABLE_SCHEMA PKTABLE_CAT, NULL PKTABLE_SCHEM,  KCU.REFERENCED_TABLE_NAME PKTABLE_NAME,"
                        + " KCU.REFERENCED_COLUMN_NAME PKCOLUMN_NAME, KCU.TABLE_SCHEMA FKTABLE_CAT, NULL FKTABLE_SCHEM, "
                        + " KCU.TABLE_NAME FKTABLE_NAME, KCU.COLUMN_NAME FKCOLUMN_NAME, KCU.POSITION_IN_UNIQUE_CONSTRAINT KEY_SEQ,"
                        + " CASE update_rule "
                        + "   WHEN 'RESTRICT' THEN 1"
                        + "   WHEN 'NO ACTION' THEN 3"
                        + "   WHEN 'CASCADE' THEN 0"
                        + "   WHEN 'SET NULL' THEN 2"
                        + "   WHEN 'SET DEFAULT' THEN 4"
                        + " END UPDATE_RULE,"
                        + " CASE DELETE_RULE"
                        + "  WHEN 'RESTRICT' THEN 1"
                        + "  WHEN 'NO ACTION' THEN 3"
                        + "  WHEN 'CASCADE' THEN 0"
                        + "  WHEN 'SET NULL' THEN 2"
                        + "  WHEN 'SET DEFAULT' THEN 4"
                        + " END DELETE_RULE,"
                        + " RC.CONSTRAINT_NAME FK_NAME,"
                        + " NULL PK_NAME,"
                        + " 6 DEFERRABILITY"
                        + " FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU"
                        + " INNER JOIN INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS RC"
                        + " ON KCU.CONSTRAINT_SCHEMA = RC.CONSTRAINT_SCHEMA"
                        + " AND KCU.CONSTRAINT_NAME = RC.CONSTRAINT_NAME"
                        + " WHERE "
                        + catalogCond("KCU.REFERENCED_TABLE_SCHEMA", parentCatalog)
                        + " AND "
                        + catalogCond("KCU.TABLE_SCHEMA", foreignCatalog)
                        + " AND "
                        + " KCU.REFERENCED_TABLE_NAME = " + escapeQuote(parentTable)
                        + " AND "
                        + " KCU.TABLE_NAME = " + escapeQuote(foreignTable)
                        + " ORDER BY FKTABLE_CAT, FKTABLE_SCHEM, FKTABLE_NAME, KEY_SEQ";

        return executeQuery(sql);
    }

    /**
     * Retrieves a description of all the data types supported by this database. They are ordered by DATA_TYPE and then by how closely the data type
     * maps to the corresponding JDBC SQL type.
     * <P>If the database supports SQL distinct types, then getTypeInfo() will return a single row with a TYPE_NAME of DISTINCT and a DATA_TYPE of
     * Types.DISTINCT. If the database supports SQL structured types, then getTypeInfo() will return a single row with a TYPE_NAME of STRUCT and a
     * DATA_TYPE of Types.STRUCT.
     * <P>If SQL distinct or structured types are supported, then information on the individual types may be obtained from the getUDTs() method.
     * <P>Each type description has the following columns: <OL> <LI><B>TYPE_NAME</B> String {@code =>} Type name <LI><B>DATA_TYPE</B> int {@code =>}
     * SQL data type from java.sql.Types <LI><B>PRECISION</B> int {@code =>} maximum precision <LI><B>LITERAL_PREFIX</B> String {@code =>} prefix used
     * to quote a literal (may be <code>null</code>) <LI><B>LITERAL_SUFFIX</B> String {@code =>} suffix used to quote a literal (may be
     * <code>null</code>) <LI><B>CREATE_PARAMS</B> String {@code =>} parameters used in creating the type (may be <code>null</code>)
     * <LI><B>NULLABLE</B> short {@code =>} can you use NULL for this type. <UL> <LI> typeNoNulls - does not allow NULL values <LI> typeNullable -
     * allows NULL values <LI> typeNullableUnknown - nullability unknown </UL> <LI><B>CASE_SENSITIVE</B> boolean{@code =>} is it case sensitive.
     * <LI><B>SEARCHABLE</B> short {@code =>} can you use "WHERE" based on this type: <UL> <LI> typePredNone - No support <LI> typePredChar - Only
     * supported with WHERE .. LIKE <LI> typePredBasic - Supported except for WHERE .. LIKE <LI> typeSearchable - Supported for all WHERE .. </UL>
     * <LI><B>UNSIGNED_ATTRIBUTE</B> boolean {@code =>} is it unsigned. <LI><B>FIXED_PREC_SCALE</B> boolean {@code =>} can it be a money value.
     * <LI><B>AUTO_INCREMENT</B> boolean {@code =>} can it be used for an auto-increment value. <LI><B>LOCAL_TYPE_NAME</B> String {@code =>} localized
     * version of type name (may be <code>null</code>) <LI><B>MINIMUM_SCALE</B> short {@code =>} minimum scale supported <LI><B>MAXIMUM_SCALE</B>
     * short {@code =>} maximum scale supported <LI><B>SQL_DATA_TYPE</B> int {@code =>} unused <LI><B>SQL_DATETIME_SUB</B> int {@code =>} unused
     * <LI><B>NUM_PREC_RADIX</B> int {@code =>} usually 2 or 10 </OL>
     * <p>The PRECISION column represents the maximum column size that the server supports for the given datatype. For numeric data, this is the
     * maximum precision.  For character data, this is the length in characters. For datetime datatypes, this is the length in characters of the
     * String representation (assuming the maximum allowed precision of the fractional seconds component). For binary data, this is the length in
     * bytes.  For the ROWID datatype, this is the length in bytes. Null is returned for data types where the column size is not applicable.
     *
     * @return a <code>ResultSet</code> object in which each row is an SQL type description
     * @throws SQLException if a database access error occurs
     */
    public ResultSet getTypeInfo() throws SQLException {
        String[] columnNames = {
                "TYPE_NAME", "DATA_TYPE", "PRECISION", "LITERAL_PREFIX", "LITERAL_SUFFIX",
                "CREATE_PARAMS", "NULLABLE", "CASE_SENSITIVE", "SEARCHABLE", "UNSIGNED_ATTRIBUTE",
                "FIXED_PREC_SCALE", "AUTO_INCREMENT", "LOCAL_TYPE_NAME", "MINIMUM_SCALE", "MAXIMUM_SCALE",
                "SQL_DATA_TYPE", "SQL_DATETIME_SUB", "NUM_PREC_RADIX"
        };
        MariaDbType[] columnTypes = {
                MariaDbType.VARCHAR, MariaDbType.INTEGER, MariaDbType.INTEGER, MariaDbType.VARCHAR, MariaDbType.VARCHAR,
                MariaDbType.VARCHAR, MariaDbType.INTEGER, MariaDbType.BIT, MariaDbType.SMALLINT, MariaDbType.BIT,
                MariaDbType.BIT, MariaDbType.BIT, MariaDbType.VARCHAR, MariaDbType.SMALLINT, MariaDbType.SMALLINT,
                MariaDbType.INTEGER, MariaDbType.INTEGER, MariaDbType.INTEGER
        };

        String[][] data = {
                {"BIT", "-7", "1", "", "", "", "1", "1", "3", "0", "0", "0", "BIT", "0", "0", "0", "0", "10"},
                {"BOOL", "-7", "1", "", "", "", "1", "1", "3", "0", "0", "0", "BOOL", "0", "0", "0", "0", "10"},
                {"TINYINT", "-6", "3", "", "", "[(M)] [UNSIGNED] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "TINYINT", "0", "0", "0", "0", "10"},
                {"TINYINT UNSIGNED", "-6", "3", "", "", "[(M)] [UNSIGNED] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "TINYINT UNSIGNED", "0", "0",
                        "0", "0", "10"},
                {"BIGINT", "-5", "19", "", "", "[(M)] [UNSIGNED] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "BIGINT", "0", "0", "0", "0", "10"},
                {"BIGINT UNSIGNED", "-5", "20", "", "", "[(M)] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "BIGINT UNSIGNED", "0", "0", "0", "0",
                        "10"},
                {"LONG VARBINARY", "-4", "16777215", "'", "'", "", "1", "1", "3", "0", "0", "0", "LONG VARBINARY", "0", "0", "0", "0", "10"},
                {"MEDIUMBLOB", "-4", "16777215", "'", "'", "", "1", "1", "3", "0", "0", "0", "MEDIUMBLOB", "0", "0", "0", "0", "10"},
                {"LONGBLOB", "-4", "2147483647", "'", "'", "", "1", "1", "3", "0", "0", "0", "LONGBLOB", "0", "0", "0", "0", "10"},
                {"BLOB", "-4", "65535", "'", "'", "", "1", "1", "3", "0", "0", "0", "BLOB", "0", "0", "0", "0", "10"},
                {"TINYBLOB", "-4", "255", "'", "'", "", "1", "1", "3", "0", "0", "0", "TINYBLOB", "0", "0", "0", "0", "10"},
                {"VARBINARY", "-3", "255", "'", "'", "(M)", "1", "1", "3", "0", "0", "0", "VARBINARY", "0", "0", "0", "0", "10"},
                {"BINARY", "-2", "255", "'", "'", "(M)", "1", "1", "3", "0", "0", "0", "BINARY", "0", "0", "0", "0", "10"},
                {"LONG VARCHAR", "-1", "16777215", "'", "'", "", "1", "0", "3", "0", "0", "0", "LONG VARCHAR", "0", "0", "0", "0", "10"},
                {"MEDIUMTEXT", "-1", "16777215", "'", "'", "", "1", "0", "3", "0", "0", "0", "MEDIUMTEXT", "0", "0", "0", "0", "10"},
                {"LONGTEXT", "-1", "2147483647", "'", "'", "", "1", "0", "3", "0", "0", "0", "LONGTEXT", "0", "0", "0", "0", "10"},
                {"TEXT", "-1", "65535", "'", "'", "", "1", "0", "3", "0", "0", "0", "TEXT", "0", "0", "0", "0", "10"},
                {"TINYTEXT", "-1", "255", "'", "'", "", "1", "0", "3", "0", "0", "0", "TINYTEXT", "0", "0", "0", "0", "10"},
                {"CHAR", "1", "255", "'", "'", "(M)", "1", "0", "3", "0", "0", "0", "CHAR", "0", "0", "0", "0", "10"},
                {"NUMERIC", "2", "65", "", "", "[(M,D])] [ZEROFILL]", "1", "0", "3", "0", "0", "1", "NUMERIC", "-308", "308", "0", "0", "10"},
                {"DECIMAL", "3", "65", "", "", "[(M,D])] [ZEROFILL]", "1", "0", "3", "0", "0", "1", "DECIMAL", "-308", "308", "0", "0", "10"},
                {"INTEGER", "4", "10", "", "", "[(M)] [UNSIGNED] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "INTEGER", "0", "0", "0", "0", "10"},
                {"INTEGER UNSIGNED", "4", "10", "", "", "[(M)] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "INTEGER UNSIGNED", "0", "0", "0", "0",
                        "10"},
                {"INT", "4", "10", "", "", "[(M)] [UNSIGNED] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "INT", "0", "0", "0", "0", "10"},
                {"INT UNSIGNED", "4", "10", "", "", "[(M)] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "INT UNSIGNED", "0", "0", "0", "0", "10"},
                {"MEDIUMINT", "4", "7", "", "", "[(M)] [UNSIGNED] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "MEDIUMINT", "0", "0", "0", "0", "10"},
                {"MEDIUMINT UNSIGNED", "4", "8", "", "", "[(M)] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "MEDIUMINT UNSIGNED", "0", "0", "0", "0",
                        "10"},
                {"SMALLINT", "5", "5", "", "", "[(M)] [UNSIGNED] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "SMALLINT", "0", "0", "0", "0", "10"},
                {"SMALLINT UNSIGNED", "5", "5", "", "", "[(M)] [ZEROFILL]", "1", "0", "3", "1", "0", "1", "SMALLINT UNSIGNED", "0", "0", "0", "0",
                        "10"},
                {"FLOAT", "7", "10", "", "", "[(M|D)] [ZEROFILL]", "1", "0", "3", "0", "0", "1", "FLOAT", "-38", "38", "0", "0", "10"},
                {"DOUBLE", "8", "17", "", "", "[(M|D)] [ZEROFILL]", "1", "0", "3", "0", "0", "1", "DOUBLE", "-308", "308", "0", "0", "10"},
                {"DOUBLE PRECISION", "8", "17", "", "", "[(M,D)] [ZEROFILL]", "1", "0", "3", "0", "0", "1", "DOUBLE PRECISION", "-308", "308", "0",
                        "0", "10"},
                {"REAL", "8", "17", "", "", "[(M,D)] [ZEROFILL]", "1", "0", "3", "0", "0", "1", "REAL", "-308", "308", "0", "0", "10"},
                {"VARCHAR", "12", "255", "'", "'", "(M)", "1", "0", "3", "0", "0", "0", "VARCHAR", "0", "0", "0", "0", "10"},
                {"ENUM", "12", "65535", "'", "'", "", "1", "0", "3", "0", "0", "0", "ENUM", "0", "0", "0", "0", "10"},
                {"SET", "12", "64", "'", "'", "", "1", "0", "3", "0", "0", "0", "SET", "0", "0", "0", "0", "10"},
                {"DATE", "91", "10", "'", "'", "", "1", "0", "3", "0", "0", "0", "DATE", "0", "0", "0", "0", "10"},
                {"TIME", "92", "18", "'", "'", "[(M)]", "1", "0", "3", "0", "0", "0", "TIME", "0", "0", "0", "0", "10"},
                {"DATETIME", "93", "27", "'", "'", "[(M)]", "1", "0", "3", "0", "0", "0", "DATETIME", "0", "0", "0", "0", "10"},
                {"TIMESTAMP", "93", "27", "'", "'", "[(M)]", "1", "0", "3", "0", "0", "0", "TIMESTAMP", "0", "0", "0", "0", "10"}
        };

        return MariaSelectResultSet.createResultSet(columnNames, columnTypes, data, connection.getProtocol());
    }

    /**
     * Retrieves a description of the given table's indices and statistics. They are ordered by NON_UNIQUE, TYPE, INDEX_NAME, and
     * ORDINAL_POSITION.<p>
     * Each index column description has the following columns: <ol> <li><B>TABLE_CAT</B> String {@code =>} table catalog (may be
     * <code>null</code>)</li> <li><B>TABLE_SCHEM</B> String {@code =>} table schema (may be <code>null</code>)</li> <li><B>TABLE_NAME</B> String
     * {@code =>} table name</li> <li><B>NON_UNIQUE</B> boolean {@code =>} Can index values be non-unique. false when TYPE is tableIndexStatistic</li>
     * <li><B>INDEX_QUALIFIER</B> String {@code =>} index catalog (may be <code>null</code>); <code>null</code> when TYPE is tableIndexStatistic</li>
     * <li><B>INDEX_NAME</B> String {@code =>} index name; <code>null</code> when TYPE is tableIndexStatistic</li> <li><B>TYPE</B> short {@code =>}
     * index type: <ul> <li> tableIndexStatistic - this identifies table statistics that are returned in conjuction with a table's index descriptions
     * <li> tableIndexClustered - this is a clustered index <li> tableIndexHashed - this is a hashed index <li> tableIndexOther - this is some other
     * style of index </ul></li> <li><B>ORDINAL_POSITION</B> short {@code =>} column sequence number within index; zero when TYPE is
     * tableIndexStatistic</li> <li><B>COLUMN_NAME</B> String {@code =>} column name; <code>null</code> when TYPE is tableIndexStatistic</li>
     * <li><B>ASC_OR_DESC</B> String {@code =>} column sort sequence, "A" {@code =>} ascending, "D" {@code =>} descending, may be <code>null</code> if
     * sort sequence is not supported; <code>null</code> when TYPE is tableIndexStatistic</li> <li><B>CARDINALITY</B> long {@code =>} When TYPE is
     * tableIndexStatistic, then this is the number of rows in the table; otherwise, it is the number of unique values in the index.</li>
     * <li><B>PAGES</B> long {@code =>} When TYPE is  tableIndexStatisic then this is the number of pages used for the table, otherwise it is the
     * number of pages used for the current index.</li> <li><B>FILTER_CONDITION</B> String {@code =>} Filter condition, if any. (may be
     * <code>null</code>)</li> </ol>
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in this database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schema a schema name; must match the schema name as it is stored in this database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param table a table name; must match the table name as it is stored in this database
     * @param unique when true, return only indices for unique values; when false, return indices regardless of whether unique or not
     * @param approximate when true, result is allowed to reflect approximate or out of data values; when false, results are requested to be accurate
     * @return <code>ResultSet</code> - each row is an index column description
     * @throws SQLException if a database access error occurs
     */
    public ResultSet getIndexInfo(String catalog, String schema, String table,
                                  boolean unique, boolean approximate) throws SQLException {

        String sql =
                "SELECT TABLE_SCHEMA TABLE_CAT, NULL TABLE_SCHEM, TABLE_NAME, NON_UNIQUE, "
                        + " TABLE_SCHEMA INDEX_QUALIFIER, INDEX_NAME, 3 TYPE,"
                        + " SEQ_IN_INDEX ORDINAL_POSITION, COLUMN_NAME, COLLATION ASC_OR_DESC,"
                        + " CARDINALITY, NULL PAGES, NULL FILTER_CONDITION"
                        + " FROM INFORMATION_SCHEMA.STATISTICS"
                        + " WHERE TABLE_NAME = " + escapeQuote(table)
                        + " AND "
                        + catalogCond("TABLE_SCHEMA", catalog)
                        + ((unique) ? " AND NON_UNIQUE = 0" : "")
                        + " ORDER BY NON_UNIQUE, TYPE, INDEX_NAME, ORDINAL_POSITION";

        return executeQuery(sql);
    }

    public boolean supportsResultSetType(int type) throws SQLException {
        return (type == ResultSet.TYPE_SCROLL_INSENSITIVE || type == ResultSet.TYPE_FORWARD_ONLY);
    }

    public boolean supportsResultSetConcurrency(int type, int concurrency) throws SQLException {
        return (type == ResultSet.TYPE_SCROLL_INSENSITIVE || type == ResultSet.TYPE_FORWARD_ONLY) && concurrency == ResultSet.CONCUR_READ_ONLY;
    }

    public boolean ownUpdatesAreVisible(int type) throws SQLException {
        return false;
    }

    public boolean ownDeletesAreVisible(int type) throws SQLException {
        return false;
    }

    public boolean ownInsertsAreVisible(int type) throws SQLException {
        return false;
    }

    public boolean othersUpdatesAreVisible(int type) throws SQLException {
        return false;
    }

    public boolean othersDeletesAreVisible(int type) throws SQLException {
        return false;
    }

    public boolean othersInsertsAreVisible(int type) throws SQLException {
        return false;
    }

    public boolean updatesAreDetected(int type) throws SQLException {
        return false;
    }

    public boolean deletesAreDetected(int type) throws SQLException {
        return false;
    }

    public boolean insertsAreDetected(int type) throws SQLException {
        return false;
    }

    public boolean supportsBatchUpdates() throws SQLException {
        return true;
    }

    /**
     * Retrieves a description of the user-defined types (UDTs) defined in a particular schema.  Schema-specific UDTs may have type
     * <code>JAVA_OBJECT</code>, <code>STRUCT</code>, or <code>DISTINCT</code>.<p>
     * Only types matching the catalog, schema, type name and type criteria are returned.  They are ordered by <code>DATA_TYPE</code>,
     * <code>TYPE_CAT</code>, <code>TYPE_SCHEM</code>  and <code>TYPE_NAME</code>.  The type name parameter may be a fully-qualified name.  In this
     * case, the catalog and schemaPattern parameters are ignored.<p>
     * Each type description has the following columns: <ol> <li><B>TYPE_CAT</B> String {@code =>} the type's catalog (may be <code>null</code>)</li>
     * <li><B>TYPE_SCHEM</B> String {@code =>} type's schema (may be <code>null</code>)</li> <li><B>TYPE_NAME</B> String {@code =>} type name</li>
     * <li><B>CLASS_NAME</B> String {@code =>} Java class name</li> <li><B>DATA_TYPE</B> int {@code =>} type value defined in java.sql.Types. One of
     * JAVA_OBJECT, STRUCT, or DISTINCT</li> <li><B>REMARKS</B> String {@code =>} explanatory comment on the type</li> <li><B>BASE_TYPE</B> short
     * {@code =>} type code of the source type of a DISTINCT type or the type that implements the user-generated reference type of the
     * SELF_REFERENCING_COLUMN of a structured type as defined in java.sql.Types (<code>null</code> if DATA_TYPE is not DISTINCT or not STRUCT with
     * REFERENCE_GENERATION = USER_DEFINED)</li> </ol>
     * <P><B>Note:</B> If the driver does not support UDTs, an empty result set is returned.
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schemaPattern a schema pattern name; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param typeNamePattern a type name pattern; must match the type name as it is stored in the database; may be a fully qualified name
     * @param types a list of user-defined types (JAVA_OBJECT, STRUCT, or DISTINCT) to include; <code>null</code> returns all types
     * @return <code>ResultSet</code> object in which each row describes a UDT
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     * @since 1.2
     */
    @Override
    public ResultSet getUDTs(String catalog, String schemaPattern, String typeNamePattern, int[] types)
            throws SQLException {
        String sql =
                "SELECT ' ' TYPE_CAT, NULL TYPE_SCHEM, ' ' TYPE_NAME, ' ' CLASS_NAME, 0 DATA_TYPE, ' ' REMARKS, 0 BASE_TYPE"
                        + " FROM DUAL WHERE 1=0";

        return executeQuery(sql);
    }

    public Connection getConnection() throws SQLException {
        return connection;
    }

    public boolean supportsSavepoints() throws SQLException {
        return true;
    }

    public boolean supportsNamedParameters() throws SQLException {
        return false;
    }

    public boolean supportsMultipleOpenResults() throws SQLException {
        return false;
    }

    public boolean supportsGetGeneratedKeys() throws SQLException {
        return true;
    }

    /**
     * Retrieves a description of the user-defined type (UDT) hierarchies defined in a particular schema in this database. Only the immediate super
     * type/ sub type relationship is modeled.
     * Only supertype information for UDTs matching the catalog, schema, and type name is returned. The type name parameter may be a fully-qualified
     * name. When the UDT name supplied is a fully-qualified name, the catalog and schemaPattern parameters are ignored.
     * If a UDT does not have a direct super type, it is not listed here. A row of the <code>ResultSet</code> object returned by this method describes
     * the designated UDT and a direct supertype. A row has the following columns: <OL> <li><B>TYPE_CAT</B> String {@code =>} the UDT's catalog (may
     * be <code>null</code>) <li><B>TYPE_SCHEM</B> String {@code =>} UDT's schema (may be <code>null</code>) <li><B>TYPE_NAME</B> String {@code =>}
     * type name of the UDT <li><B>SUPERTYPE_CAT</B> String {@code =>} the direct super type's catalog (may be <code>null</code>)
     * <li><B>SUPERTYPE_SCHEM</B> String {@code =>} the direct super type's schema (may be <code>null</code>) <li><B>SUPERTYPE_NAME</B> String {@code
     * =>} the direct super type's name </OL>
     * <P><B>Note:</B> If the driver does not support type hierarchies, an empty result set is returned.
     *
     * @param catalog a catalog name; "" retrieves those without a catalog; <code>null</code> means drop catalog name from the selection criteria
     * @param schemaPattern a schema name pattern; "" retrieves those without a schema
     * @param typeNamePattern a UDT name pattern; may be a fully-qualified name
     * @return a <code>ResultSet</code> object in which a row gives information about the designated UDT
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     * @since 1.4
     */
    public ResultSet getSuperTypes(String catalog, String schemaPattern, String typeNamePattern)
            throws SQLException {
        String sql =
                "SELECT  ' ' TYPE_CAT, NULL TYPE_SCHEM, ' ' TYPE_NAME, ' ' SUPERTYPE_CAT, ' ' SUPERTYPE_SCHEM, ' '  SUPERTYPE_NAME"
                        + " FROM DUAL WHERE 1=0";

        return executeQuery(sql);
    }

    /**
     * Retrieves a description of the table hierarchies defined in a particular schema in this database.
     * <P>Only supertable information for tables matching the catalog, schema and table name are returned. The table name parameter may be a fully-
     * qualified name, in which case, the catalog and schemaPattern parameters are ignored. If a table does not have a super table, it is not listed
     * here. Supertables have to be defined in the same catalog and schema as the sub tables. Therefore, the type description does not need to include
     * this information for the supertable.
     * <P>Each type description has the following columns: <OL> <li><B>TABLE_CAT</B> String {@code =>} the type's catalog (may be <code>null</code>)
     * <li><B>TABLE_SCHEM</B> String {@code =>} type's schema (may be <code>null</code>) <li><B>TABLE_NAME</B> String {@code =>} type name
     * <li><B>SUPERTABLE_NAME</B> String {@code =>} the direct super type's name </OL>
     * <P><B>Note:</B> If the driver does not support type hierarchies, an empty result set is returned.
     *
     * @param catalog a catalog name; "" retrieves those without a catalog; <code>null</code> means drop catalog name from the selection criteria
     * @param schemaPattern a schema name pattern; "" retrieves those without a schema
     * @param tableNamePattern a table name pattern; may be a fully-qualified name
     * @return a <code>ResultSet</code> object in which each row is a type description
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     * @since 1.4
     */
    public ResultSet getSuperTables(String catalog, String schemaPattern, String tableNamePattern)
            throws SQLException {
        String sql =
                "SELECT  ' ' TABLE_CAT, ' ' TABLE_SCHEM, ' ' TABLE_NAME, ' ' SUPERTABLE_NAME FROM DUAL WHERE 1=0";
        return executeQuery(sql);
    }

    /**
     * Retrieves a description of the given attribute of the given type for a user-defined type (UDT) that is available in the given schema and
     * catalog.
     * Descriptions are returned only for attributes of UDTs matching the catalog, schema, type, and attribute name criteria. They are ordered by
     * <code>TYPE_CAT</code>, <code>TYPE_SCHEM</code>, <code>TYPE_NAME</code> and <code>ORDINAL_POSITION</code>. This description does not contain
     * inherited attributes.
     * The <code>ResultSet</code> object that is returned has the following columns: <OL> <li><B>TYPE_CAT</B> String {@code =>} type catalog (may be
     * <code>null</code>) <li><B>TYPE_SCHEM</B> String {@code =>} type schema (may be <code>null</code>) <li><B>TYPE_NAME</B> String {@code =>} type
     * name <li><B>ATTR_NAME</B> String {@code =>} attribute name <li><B>DATA_TYPE</B> int {@code =>} attribute type SQL type from java.sql.Types
     * <li><B>ATTR_TYPE_NAME</B> String {@code =>} Data source dependent type name. For a UDT, the type name is fully qualified. For a REF, the type
     * name is fully qualified and represents the target type of the reference type. <li><B>ATTR_SIZE</B> int {@code =>} column size.  For char or
     * date types this is the maximum number of characters; for numeric or decimal types this is precision. <li><B>DECIMAL_DIGITS</B> int {@code =>}
     * the number of fractional digits. Null is returned for data types where DECIMAL_DIGITS is not applicable. <li><B>NUM_PREC_RADIX</B> int {@code
     * =>} Radix (typically either 10 or 2) <li><B>NULLABLE</B> int {@code =>} whether NULL is allowed <UL> <li> attributeNoNulls - might not allow
     * NULL values <li> attributeNullable - definitely allows NULL values <li> attributeNullableUnknown - nullability unknown </UL> <li><B>REMARKS</B>
     * String {@code =>} comment describing column (may be <code>null</code>) <li><B>ATTR_DEF</B> String {@code =>} default value (may be
     * <code>null</code>) <li><B>SQL_DATA_TYPE</B> int {@code =>} unused <li><B>SQL_DATETIME_SUB</B> int {@code =>} unused
     * <li><B>CHAR_OCTET_LENGTH</B> int {@code =>} for char types the maximum number of bytes in the column <li><B>ORDINAL_POSITION</B> int {@code =>}
     * index of the attribute in the UDT (starting at 1) <li><B>IS_NULLABLE</B> String  {@code =>} ISO rules are used to determine the nullability for
     * a attribute. <UL> <li> YES           --- if the attribute can include NULLs <li> NO            --- if the attribute cannot include NULLs <li>
     * empty string  --- if the nullability for the attribute is unknown </UL> <li><B>SCOPE_CATALOG</B> String {@code =>} catalog of table that is the
     * scope of a reference attribute (<code>null</code> if DATA_TYPE isn't REF) <li><B>SCOPE_SCHEMA</B> String {@code =>} schema of table that is the
     * scope of a reference attribute (<code>null</code> if DATA_TYPE isn't REF) <li><B>SCOPE_TABLE</B> String {@code =>} table name that is the scope
     * of a reference attribute (<code>null</code> if the DATA_TYPE isn't REF) <li><B>SOURCE_DATA_TYPE</B> short {@code =>} source type of a distinct
     * type or user-generated Ref type,SQL type from java.sql.Types (<code>null</code> if DATA_TYPE isn't DISTINCT or user-generated REF) </OL>
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schemaPattern a schema name pattern; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param typeNamePattern a type name pattern; must match the type name as it is stored in the database
     * @param attributeNamePattern an attribute name pattern; must match the attribute name as it is declared in the database
     * @return a <code>ResultSet</code> object in which each row is an attribute description
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     * @since 1.4
     */
    public ResultSet getAttributes(String catalog, String schemaPattern, String typeNamePattern,
                                   String attributeNamePattern) throws SQLException {

        String sql =
                "SELECT ' ' TYPE_CAT, ' ' TYPE_SCHEM, ' ' TYPE_NAME, ' ' ATTR_NAME, 0 DATA_TYPE,"
                        + " ' ' ATTR_TYPE_NAME, 0 ATTR_SIZE, 0 DECIMAL_DIGITS, 0 NUM_PREC_RADIX, 0 NULLABLE,"
                        + " ' ' REMARKS, ' ' ATTR_DEF,  0 SQL_DATA_TYPE, 0 SQL_DATETIME_SUB, 0 CHAR_OCTET_LENGTH,"
                        + " 0 ORDINAL_POSITION, ' ' IS_NULLABLE, ' ' SCOPE_CATALOG, ' ' SCOPE_SCHEMA, ' ' SCOPE_TABLE,"
                        + " 0 SOURCE_DATA_TYPE"
                        + " FROM DUAL "
                        + " WHERE 1=0";

        return executeQuery(sql);
    }

    public boolean supportsResultSetHoldability(int holdability)
            throws SQLException {
        return holdability == ResultSet.HOLD_CURSORS_OVER_COMMIT;
    }

    public int getResultSetHoldability() throws SQLException {
        return ResultSet.HOLD_CURSORS_OVER_COMMIT;
    }

    public int getDatabaseMajorVersion() throws SQLException {
        return connection.getProtocol().getMajorServerVersion();
    }

    public int getDatabaseMinorVersion() throws SQLException {
        return connection.getProtocol().getMinorServerVersion();
    }

    @Override
    public int getJDBCMajorVersion() throws SQLException {
        return 4;
    }

    @Override
    public int getJDBCMinorVersion() throws SQLException {
        return 0;
    }

    @Override
    public int getSQLStateType() throws SQLException {
        return sqlStateSQL;
    }

    public boolean locatorsUpdateCopy() throws SQLException {
        return false;
    }

    public boolean supportsStatementPooling() throws SQLException {
        return false;
    }

    public RowIdLifetime getRowIdLifetime() throws SQLException {
        return RowIdLifetime.ROWID_UNSUPPORTED;
    }

    public boolean supportsStoredFunctionsUsingCallSyntax() throws SQLException {
        return true;
    }

    public boolean autoCommitFailureClosesAllResultSets() throws SQLException {
        return false;
    }

    /**
     * Retrieves a list of the client info properties that the driver supports. The result set contains the following columns
     * <ol>
     *     <li>NAME String : The name of the client info property</li>
     *     <li>MAX_LEN int : The maximum length of the value for the property</li>
     *     <li>DEFAULT_VALUE String : The default value of the property</li>
     *     <li>DESCRIPTION String : A description of the property.
     *     This will typically contain information as to where this property is stored in the database.</li>
     * </ol>
     * The ResultSet is sorted by the NAME column
     * @return A ResultSet object; each row is a supported client info property
     * @throws SQLException if connection error occur
     */
    public ResultSet getClientInfoProperties() throws SQLException {
        ColumnInformation[] columns = new ColumnInformation[4];
        columns[0] = ColumnInformation.create("NAME", MariaDbType.STRING);
        columns[1] = ColumnInformation.create("MAX_LEN", MariaDbType.INTEGER);
        columns[2] = ColumnInformation.create("DEFAULT_VALUE", MariaDbType.STRING);
        columns[3] = ColumnInformation.create("DESCRIPTION", MariaDbType.STRING);


        List<byte[][]> rows = new ArrayList<>(3);
        rows.add(new byte[][] {
                "ApplicationName".getBytes(),
                new byte[] {(byte) 49, (byte) 54, (byte) 55, (byte) 55, (byte) 55, (byte) 50, (byte) 49, (byte) 53},  //16Mb
                new byte[]{},
                "The name of the application currently utilizing the connection".getBytes()
        });
        rows.add(new byte[][] {
                "ClientUser".getBytes(),
                new byte[] {(byte) 49, (byte) 54, (byte) 55, (byte) 55, (byte) 55, (byte) 50, (byte) 49, (byte) 53},  //16Mb
                new byte[]{},
                ("The name of the user that the application using the connection is performing work for. "
                        + "This may not be the same as the user name that was used in establishing the connection.").getBytes()
        });
        rows.add(new byte[][] {
                "ClientHostname".getBytes(),
                new byte[] {(byte) 49, (byte) 54, (byte) 55, (byte) 55, (byte) 55, (byte) 50, (byte) 49, (byte) 53},  //16Mb
                new byte[]{},
                "The hostname of the computer the application using the connection is running on".getBytes()
        });

        return new MariaSelectResultSet(columns, rows, connection.getProtocol(), ResultSet.TYPE_SCROLL_INSENSITIVE);
    }

    /**
     * Retrieves a description of the  system and user functions available in the given catalog.
     * Only system and user function descriptions matching the schema and function name criteria are returned.  They are ordered by
     * <code>FUNCTION_CAT</code>, <code>FUNCTION_SCHEM</code>, <code>FUNCTION_NAME</code> and <code>SPECIFIC_ NAME</code>.
     * <P>Each function description has the the following columns: <OL> <li><B>FUNCTION_CAT</B> String {@code =>} function catalog (may be
     * <code>null</code>) <li><B>FUNCTION_SCHEM</B> String {@code =>} function schema (may be <code>null</code>) <li><B>FUNCTION_NAME</B> String
     * {@code =>} function name.  This is the name used to invoke the function <li><B>REMARKS</B> String {@code =>} explanatory comment on the
     * function <li><B>FUNCTION_TYPE</B> short {@code =>} kind of function: <UL> <li>functionResultUnknown - Cannot determine if a return value or
     * table will be returned <li> functionNoTable- Does not return a table <li> functionReturnsTable - Returns a table </UL> <li><B>SPECIFIC_NAME</B>
     * String  {@code =>} the name which uniquely identifies this function within its schema.  This is a user specified, or DBMS generated, name that
     * may be different then the <code>FUNCTION_NAME</code> for example with overload functions </OL>
     * A user may not have permission to execute any of the functions that are returned by <code>getFunctions</code>
     *
     * @param catalog a catalog name; must match the catalog name as it is stored in the database; "" retrieves those without a catalog;
     * <code>null</code> means that the catalog name should not be used to narrow the search
     * @param schemaPattern a schema name pattern; must match the schema name as it is stored in the database; "" retrieves those without a schema;
     * <code>null</code> means that the schema name should not be used to narrow the search
     * @param functionNamePattern a function name pattern; must match the function name as it is stored in the database
     * @return <code>ResultSet</code> - each row is a function description
     * @throws SQLException if a database access error occurs
     * @see #getSearchStringEscape
     * @since 1.6
     */
    public ResultSet getFunctions(String catalog, String schemaPattern, String functionNamePattern)
            throws SQLException {
        String sql =
                "SELECT ROUTINE_SCHEMA FUNCTION_CAT,NULL FUNCTION_SCHEM, ROUTINE_NAME FUNCTION_NAME,"
                        + " ROUTINE_COMMENT REMARKS," + functionNoTable + " FUNCTION_TYPE, SPECIFIC_NAME "
                        + " FROM INFORMATION_SCHEMA.ROUTINES "
                        + " WHERE "
                        + catalogCond("ROUTINE_SCHEMA", catalog)
                        + " AND "
                        + patternCond("ROUTINE_NAME", functionNamePattern)
                        + " AND ROUTINE_TYPE='FUNCTION'";

        return executeQuery(sql);
    }

    public <T> T unwrap(final Class<T> iface) throws SQLException {
        return null;
    }

    public boolean isWrapperFor(final Class<?> iface) throws SQLException {
        return false;
    }

}