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pythonsqlalchemyalembic

Alembic drops indexes for foreign keys

I have a column address_id = db.Column(db.Integer, db.ForeignKey(Address.id, ondelete='CASCADE'), index=True). Autogenerating a migration with Alembic always adds a drop_index operation.

op.drop_index('address_id', 'companies')

Why does this happen every time I generate a migration?

Solution

  • This is a known bug in Alembic 0.6.1. Upgrade to 0.6.2 or newer and the problem will go away.