psychopg2 complaining that a table doesn't exist after migrations

[andre-qumulo]

I am migrating a SqlAlchemy 1.3 project with Alembic 1.4.2 to SqlAlchemy 2.x and Alembic 1.13.1

I am running into a very confusing problem where when I run a db.session.execute(text('INSERT INTO ... into a table that is dropped and then recreated in a migration I get an error that sqlalchemy.exc.ProgrammingError: (psycopg2.errors.UndefinedTable) relation "some_table_name" does not exist.

I am trying to understand what to try to try and figure out the issue.

More details are here: https://stackoverflow.com/questions/78481263/sqlalchemy-relation-does-not-exist-after-flask-migrate

[CaselIT]

Hi,

Well first thing to try would be to verify it the table is indeed there using psql of another similar tool

[andre-qumulo]

I'm wondering if it's a problem with my env.py file.

We had a file that looked similar to this: https://gist.github.com/sairamkrish/e583abdf7c21aed987754f9a2e252cbd
but I'm seeing TypeError: alembic.context.configure() got multiple values for keyword argument 'render_as_batch' errors when I change the arguments to context.configure( between the run_migrations_offline and run_migrations_online functions.

Is there an example of what it should look like now?

[andre-qumulo]

I was able to get into the DB via psql after the migration should have ran (it looks like we initialize a local host) and \d shows no relations. Do you think this is a problem with Alembic or flask-migrate that we're using?

[CaselIT]

I would start by using a normal postgresql configuration.
If that works then try to understand what are the limitations of your custom setup and do the appropriate changes.

I'm also not sure why you are trying to use alembic with a temporary volatile database, it may be easier to just recreate the schema from scratch using metadata.create_all

[andre-qumulo]

So these are unit/integration tests that allow us to run the migration against a temporary DB to ensure it won't destroy our production one.
I have been able to use psql to log into the DB as it's running on localhost.

Somehow I fixed this by replacing our env.py file with the one from flask-migrate's repo and removing any references to running the migrations as sql