Chapter 4 problem with db_viewer.py

[PaulKlasmann]

When running the chapter 4 program db_viewer.py I get the following error:

Traceback (most recent call last): File "/home/xxx/Documents/MyPython/db_viewer.py", line 95, in loadDatabase self.table_names = self.engine.table_names() AttributeError: 'Engine' object has no attribute 'table_names'

I read somewhere that it happens because of a change between the older and current version of the library. Please can someone give the "new" way to do the loading of the database with sqlalchemy? Thank you.

[arichel]

Hello Paul,

Change 1:

for the current SQLAlchemy release you need to change line 86 in method loadDatabase from:
self.table_names = self.engine.table_names()
to
inspector = inspect(self.engine)
self.table_names = inspector.get_table_names()
and import
from sqlalchemy import inspect

Change 2:

On line 49 of method loadTable change:
metadata = MetaData(self.engine)
to
metadata = MetaData()
metadata.reflect(self.engine)

Change 3

and on line 54 of the same method change:
mapper(GenericDBClass, table)
to
mapper_registry = registry()
mapper_registry.map_imperatively(GenericDBClass, table)
and also import
from sqlalchemy.orm import registry

Hope this solves your issues.