KeyError on connecting to DB
I have build my own SQLAlchemy Dialect for a DB. Dialect works and is tested. I try to run a simple migration (create table) against DB (schema exists). If I use a non-existing schema in the connection string I get a DB error ("Schema does not exist). So basic connectivity seems to be fine.
When using the correct schema, I get the following error in alembic:
alembic/ddl/impl.py", line 50, in get_by_dialect return _impls[dialect.name] KeyError: 'mydb'
I briefly looked at the code. Which part of alembic is responsible for filling the _impls dict? How can my dialect end up there? Do I have to announce my dialect to alembic?