sqlalchemy-redshift: Redshift does not support sequences

I think I got it working by setting

RedshiftDialect.supports_sequences = False
RedshiftDialect.preexecute_autoincrement_sequences = False
**RedshiftDialect.postfetch_lastrowid = True**

I’m still debugging things, but so far there’s no been any primary key related errors.

Any updates on this?

@aboedo done

Hey nwbvt, thank you so much! It kind of works. The ‘(psycopg2.ProgrammingError) relation “tablename_model_id_seq” does not exist’ error is solved by setting those two variables to False, but now I’m getting the following:

sqlalchemy.orm.exc.FlushError: Instance [ENTITY] has a NULL identity key. 
If this is an auto-generated value, check that the database table allows generation of new primary key values, and that the mapped Column object is configured to expect these generated values. 
Ensure also that this flush() is not occurring at an inappropriate time, such as within a load() event.

I guess there should be a

SELECT MAX([id_column])
FROM [entity_table]

immediately following the INSERT INTO [entity_table] statement.

I’m kind of new to SqlAlchemy, do you have any idea where/what should I modify in sqlalchemy_redshift to add this?

Thanks again,

Mario