test_db_sync_downgrade_then_upgrade fails no such index: ix_images_deleted

[Ewan Mellor]

test_db_sync_downgrade_then_upgrade fails with

OperationalError: (OperationalError) no such index: ix_images_deleted u'\nDROP INDEX ix_images_deleted' ()

when using virtualenv on Ubuntu 10.10 and lp:glance revno 90.

Note that https://bugs.launchpad.net/glance/+bug/731030 is superficially similar, but the failure mode and environment are different.

Note also that Jay Pipes seems to have reported something along these lines against sqlalchemy-migrate: http://code.google.com/p/sqlalchemy-migrate/issues/detail?id=117.

[Jay Pipes (jaypipes)]

Yup, and not a single comment back from any of the SA-migrate people. It's been very frustrating. :(

The reason this happens is two-fold: SQLite does not support DROP COLUMN and sa-migrate attempts to work around this with a hack that creates a temporary table with the new schema and then drops the old one.

I'm working on the whole migration functionality in a branch. Hopefully, we'll have this resolved soon...

Note that we've been unable to reproduce this in any non-SQLite data store. If you've seen this happen in MySQL or PostgreSQL, please do let us know!

[Jay Pipes (jaypipes)]

Ewan, would you mind verifying this bug again now that the fixes for migration scripts are in trunk? Thanks!

[Ewan Mellor (ewanmellor)]

Verified fixed as of lp:glance revno 100. Note that the cited unit test (test_db_sync_downgrade_then_upgrade) has gone, but I can confirm that all the TestMigrations tests are passing in my environment.