Re: Optimize date query for large child tables: GiST or GIN? - Mailing list pgsql-performance

On Wed, 19 May 2010, David Jarvis wrote:
>      extract( YEAR FROM m.taken ) BETWEEN 1900 AND 2009 AND

That portion of the WHERE clause cannot use an index on m.taken. Postgres
does not look inside functions (like extract) to see if something
indexable is present. To get an index to work, you could create an index
on (extract(YEAR FROM m.taken)).

Matthew

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