python - insert into table from another table with alembic -


i have 2 tables linked id (their foreign key). want write alembic script to:

1.get rows in table #1 column_name = null

2.for each row, insert new row table #2.

3.update table #1’s null column_name fields newly inserted fields in table #2 (where table#1.col.id = table#2.col.id):

how can newly inserted ids in table #2 in order update column_name in table #1? following approach correct:

def upgrade():     conn = op.get_bind()      rows = conn.execute(         sa.select([             table1.id.label('id'),         ]).where(             table1.column_name_is_(none)         )     ).fetchall()

how can optimize use of update , insert?


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