Re: VACUUM ANALYZE downgrades performance

Hi Rod!

Thomas> Index scans are not always faster, and the planner/optimizer knows
Thomas> this. VACUUM ANALYZE is best run when a large proportion of data
Thomas> has been updated/loaded or in the off hours to refresh the
Thomas> statistics on large datasets.
>> While I agree that generally this is true, look how stupid this
>> behavior looks in this particular case: A developer creates a table and
>> index, knowing that the table will be large and will be intensively
>> used. An admin runs 'VACUUM ANALYZE' when table is occasionally empty,
>> and next, say, 1 day, until another 'VACUUM ANALYZE' starts, the index
>> is simply not used! Sure you don't suppose to run 'VACUUM ANALYZE'
>> every 5 minutes as a solution, right?

Rod> You might want to try this on the next 8.0 beta to come out, or
Rod> against CVS. Tom recently applied some changes which should mitigate
Rod> this situation.

But this would affect only VACUUM, and not ANALYZE, right?

--
Sincerely,
Dmitry Karasik

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