ClickHouse: triage smoke ClickHouse#9 new families — AggState float drift + Enum UPDATE

Two new reproducer families from smoke ClickHouse#9 triaged:

1. AggregateStateRoundtrip (3 reproducers): sum(c0) vs finalizeAggregation(
   arrayReduce('sumState', groupArray(c0))) returned different floats. Root
   cause is float-arithmetic non-associativity -- sum() over an unsorted table
   reads rows in storage order, sumState over a groupArray reads in array
   order; for floats, different orders produce different ULP-level sums.
   Not a CH bug. Restrict the oracle's sum branch to integer columns only.
   min/max/count are order-independent and safe on float.

2. SEMR (2) + AggregateStateRoundtrip (1): ALTER UPDATE assigning a numeric
   literal to an Enum column with CANNOT_CONVERT_TYPE. The mutation generator
   was type-blind. Filter target columns to plain primitives / Decimal /
   FixedString / DateTime64 -- skips Enum / composite / geo / JSON-family /
   AggregateFunction columns that can't accept arbitrary integer expressions.

Author: fm4v

src/sqlancer/clickhouse/gen/ClickHouseMutationGenerator.java

@@ -53,7 +53,21 @@ public static SQLQueryAdapter getQuery(ClickHouseGlobalState state) {
         StringBuilder sb = new StringBuilder();
         switch (kind) {
         case ALTER_UPDATE:
-            ClickHouseColumn updateCol = Randomly.fromList(cols);
+            // Filter target columns to types where the existing expression generator produces
+            // well-typed values. Enum / composite / geo / JSON-family rejects arbitrary integer
+            // expressions with CANNOT_CONVERT_TYPE; aliased / materialised columns can't be
+            // updated. Restrict to plain primitives.
+            List<ClickHouseColumn> updatable = cols.stream().filter(c -> {
+                sqlancer.clickhouse.ClickHouseType term = c.getType().getTypeTerm().unwrap();
+                return term instanceof sqlancer.clickhouse.ClickHouseType.Primitive
+                        || term instanceof sqlancer.clickhouse.ClickHouseType.Decimal
+                        || term instanceof sqlancer.clickhouse.ClickHouseType.FixedString
+                        || term instanceof sqlancer.clickhouse.ClickHouseType.DateTime64Type;
+            }).collect(Collectors.toList());
+            if (updatable.isEmpty()) {
+                throw new IgnoreMeException();
+            }
+            ClickHouseColumn updateCol = Randomly.fromList(updatable);
             // Use an expression generator over the *other* columns so the assignment can't be a
             // pure recursive reference; this isn't strictly required by CH but keeps test variance
             // higher.

src/sqlancer/clickhouse/oracle/aggstate/ClickHouseAggregateStateRoundtripOracle.java

@@ -55,11 +55,26 @@ public void check() throws SQLException {
         if (numericCols.isEmpty()) {
             throw new IgnoreMeException();
         }
+        // For sum/avg, restrict to INTEGER columns -- float-arithmetic is non-associative, so
+        // sum(unsorted_table) and sumState(groupArray(unsorted_table)) can return different
+        // floats depending on read order. min/max/count are order-independent and safe on any
+        // numeric type.
+        String aggName = Randomly.fromOptions("min", "max", "count", "sum");
+        if (aggName.equals("sum")) {
+            List<ClickHouseColumn> intCols = numericCols.stream().filter(c -> {
+                com.clickhouse.data.ClickHouseDataType t = c.getType().getType();
+                return t != com.clickhouse.data.ClickHouseDataType.Float32
+                        && t != com.clickhouse.data.ClickHouseDataType.Float64
+                        && t != com.clickhouse.data.ClickHouseDataType.Decimal;
+            }).collect(Collectors.toList());
+            if (intCols.isEmpty()) {
+                throw new IgnoreMeException();
+            }
+            numericCols = intCols;
+        }
         ClickHouseColumn col = Randomly.fromList(numericCols);
         String fqTable = state.getDatabaseName() + "." + table.getName();
 
-        String aggName = Randomly.fromOptions("sum", "min", "max", "count");
-
         String lhsQuery = "SELECT " + aggName + "(" + col.getName() + ") FROM " + fqTable;
         String rhsQuery = "SELECT finalizeAggregation(arrayReduce('" + aggName + "State', groupArray("
                 + col.getName() + "))) FROM " + fqTable;