driscollis
Chapter 4 problem with db_viewer.py
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.
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.
