Re: caching indexes and pages?

In response to Thomas Finneid :
>
> Hi I am developing a database and have a couple of questions I havent
> found an answer to yet.
>
> 1) how do I find the size of an index, i.e. the size on disk?

http://www.postgresql.org/docs/8.3/interactive/functions-admin.html
http://andreas.scherbaum.la/blog/archives/282-table-size,-database-size.html

>
> 2) I have a query that is taking a long time to complete because the

How long is a long time? *g*

> table is about 120GB large. Its only returning 2000 rows, so in
> principle it should be fast. But because the data is spread across the
> table, I am assuming it needs to do a lot of disk access to fetch the
> appropriate pages. Since the amount of data is so large I am also

Please execute your query with an additionally 'explain analyse select
...' and look at the output. Maybe there are no propper index for your
select.

Regards, Andreas
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Andreas Kretschmer
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