Zeugswetter Andreas IZ5 <Andreas(dot)Zeugswetter(at)telecom(dot)at> writes:
>> Yes, I think we index nulls. What are partial indexes?
>>
> A create index statement that accepts a where condition. All
> rows that satisfy the where condition are indexed, others not.
> This needs intelligence in the optimizer.
> This was in postgresql code some time ago, but was removed
> for some reason I don't remember.
It was? There's still a ton of code in the optimizer to support it
(a big chunk of indxqual.c is for testing index predicates).
regards, tom lane