Re: SELECT DISTINCT very slow

Hello

when you use older pg than 8.3, please, use GROUP BY.

SELECT field FROM table GROUP BY field.

Regards
Pavel Stehule

2009/7/9 Ben Harper <rogojin(at)gmail(dot)com>:
> Hi,
> Can anybody explain this:
>
> Records: 600,000
> Field Width: Approximately 20 UTF8 characters - type is VARCHAR(25)
> Field is Indexed.
>
> SELECT DISTINCT field FROM table;
>
> Takes about 6 seconds. There are 111 distinct items.
>
> On Sqlite, and another place where I have a B+Tree, this query is
> faster than my eye can measure.
>
> Is this a well known issue?
>
> Thanks,
> Ben
>
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