Kevin Grittner [Kevin.Grittner@xxxxxxxxxxxx] wrote:
Is there any correlation between ts_id and ts_interval_start_time?
only vaguely: increasing ts_interval_start_time implies increasing ts_id
but there may be many rows (100,000's) with the same ts_interval_start_time
Perhaps if you tried min and max with different time ranges it would
find a row on a backward scan faster. It'll take ten times as long if
it has to scan through ten times as many rows to find a match.
it looks like there are fewer rows backwards than forwards:
cemdb=> select count(*) from ts_stats_transet_user_interval where
ts_interval_start_time < '2009-6-16 01:00';
count
----------
32100000
(1 row)
cemdb=> select count(*) from ts_stats_transet_user_interval where
ts_interval_start_time >= '2009-6-16 02:00';
count
----------
13500000
(1 row)
I don't suppose you have an index on ts_interval_start_time?
there is an index. I mentioned this in my orginal posting.
Thanks,
Brian
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