David Wilson wrote:
On another table in the same database with a much smaller number of
total rows (~15m rows), I have the exact same situation- but in this
case the index on the datestamp column *is* used:
Have you run ANALYZE on both tables?
It might be worth increasing the stats collected on the datestamp column
(or all columns in the table), re-running ANALYZE on the table, and
seeing what happens.
Also, is there any chance that that's a lot more variation in datestamp
values in your problem table than the one where the index is used?
--
Craig Ringer
