Hi Richard,
Thanks for your prompt reply. It fixed the problem. Just one more question: Do I need to create an index for FKs?
You don't _need_ to, but on the referring side (e.g. table GCTBALLOT in your example) PostgreSQL won't create one automatically.
Of course, the primary-key side will already have an index being used as part of the constraint.
I've cc:ed the list on this, the question pops up quite commonly.
-- Richard Huxton Archonet Ltd
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