Re: analyzing intermediate query
От
Andrus
Тема
Re: analyzing intermediate query
Дата
Msg-id
72246E216337406EAD285F5A45533672@andrusnotebook
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analyzing intermediate query "Andrus" <kobruleht2@hot.ee>
Re: analyzing intermediate query PFC <lists@peufeu.com>
Re: analyzing intermediate query "Andrus" <kobruleht2@hot.ee>
Re: analyzing intermediate query PFC <lists@peufeu.com>
Re: analyzing intermediate query "Andrus" <kobruleht2@hot.ee>
Re: analyzing intermediate query PFC <lists@peufeu.com>
Re: analyzing intermediate query "Andrus" <kobruleht2@hot.ee>
Re: analyzing intermediate query Scott Carey <scott@richrelevance.com>
Re: analyzing intermediate query "Andrus" <kobruleht2@hot.ee>
Re: analyzing intermediate query Scott Carey <scott@richrelevance.com>
> Oh, I just thought about something, I don't remember in which version it > was added, but : > > EXPLAIN ANALYZE SELECT sum(column1) FROM (VALUES ...a million > ntegers... ) AS v > > Postgres is perfectly happy with that ; it's either a bit slow (about 1 > second) or very fast depending on how you view things... I tried in 8.1.4 select * from (values (0)) xx but got ERROR: syntax error at or near ")" SQL state: 42601 Character: 26 Even if this works this may be not solution: I need to apply distinct to temporary table. Temporary table may contain duplicate values and without DISTINCT join produces invalid result. Temporary table itself is created from data from server tables, it is not generated from list. I can use SELECT dok.* FROM dok WHERE dokumnr IN (SELECT dokumnr FROM temptbl) but this seems never use bitmap index scan in 8.1.4 Sadly, creating second temporary table from first temporary table specially for this query seems to be only solution. When materialized row count will be added so that statistics is exact and select count(*) from tbl runs fast ? Andrus.
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