Improve Seq scan performance
От | Lutischán Ferenc |
---|---|
Тема | Improve Seq scan performance |
Дата | |
Msg-id | 4917D9C3.9060001@gmail.com обсуждение исходный текст |
Ответы |
Re: Improve Seq scan performance
Re: Improve Seq scan performance |
Список | pgsql-performance |
Dear List, I would like to improve seq scan performance. :-) I have many cols in a table. I use only 1 col for search on it. It is indexed with btree with text_pattern_ops. The search method is: r like '%aaa%' When I make another table with only this col values, the search time is better when the data is cached. But wronger when the data isn't in cache. I think the following: - When there is a big table with many cols, the seq search is read all cols not only searched. - If we use an index with full values of a col, it is possible to seq scan over the index is make better performance (lower io with smaller data). It is possible to make an index on the table, and make a seq index scan on this values? Thanks for helping. Best Regards, Ferenc
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