I'm trying to run an alter_column operation from a Boolean type column to SmallInteger on Oracle.
According to the documentation: "...Type changes which are against the SQLAlchemy “schema” types Boolean <http://www.sqlalchemy.org/docs/core/type_basics.html#sqlalchemy.types.Boolean> and Enum <http://www.sqlalchemy.org/docs/core/type_basics.html#sqlalchemy.types.Enum> may also add or drop constraints which accompany those types on backends that don’t support them natively. The existing_server_default argument is used in this case as well to remove a previous constraint...." Does this mean that the alter column should work out-of-the-box or do I have to remove the constraint myself because I'm getting the following error on alembic 0.8.3 (sqlalchemy 1.0.9): sqlalchemy.exc.CompileError: Can't emit DROP CONSTRAINT for constraint CheckConstraint(<sqlalchemy.sql.elements.BinaryExpression object at 0x28a9b10>, name='_unnamed_', table=Table('t_message', MetaData(bind=None), Column('is_bulletin', Boolean(), table=<t_message>), schema=None), _create_rule=<sqlalchemy.util.langhelpers.portable_instancemethod object at 0x289ac68>, _type_bound=True); it has no name And on a previous version (alembic 0.6.5, sqlalchemy 0.9.7) I got the following error: sqlalchemy.exc.DatabaseError: (DatabaseError) ORA-02443: Cannot drop constraint - nonexistent constraint 'ALTER TABLE t_message DROP CONSTRAINT None' {} Your help will be appreciated... -- You received this message because you are subscribed to the Google Groups "sqlalchemy-alembic" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
