Re: Performance degradation 8.4 -> 9.1

On 18 Listopad 2011, 11:39, Greg Smith wrote:
> On 11/17/2011 02:24 PM, Joseph Shraibman wrote:
>> This query is taking much longer on 9.1 than it did on 8.4. Why is it
>> using a seq scan?
>>
>
> To answer that question in all cases, it's necessary to know a) the
> query, b) the PostgreSQL version, c) the table definitions including
> what indexes exist, d) the statistics collected about each column, (e)
> the sizes of all the indexes on any referenced table, and (f) the server
> parameters. Sometimes you can get useful feedback from just the first

And (g) EXPLAIN ANALYZE plans for the queries - if possible from both
versions. Use explain.depesz.com to post it.

Tomas