Re: Index usage problem on 8.3.3

Jeff Frost <jeff@frostconsultingllc.com> writes:
> Tom Lane wrote:
>> Okay.  What that means is that the indexes were created on data that had
>> already been inserted and updated to some extent, resulting in
>> HOT-update chains that turned out to be illegal for the new indexes.
>> The way we deal with this is to mark the indexes as not usable by any
>> query that can still see the dead HOT-updated tuples.

> Any idea why I don't see it on 8.3.4?

I think it's more likely some small difference in your test conditions
than any real version-to-version difference.  In particular I think the
"still see" test might be influenced by the ages of transactions running
concurrently.

            regards, tom lane