Re: [SQL] 7.3.1 index use / performance

On Tue, 7 Jan 2003, Tomasz Myrta wrote:

> Maybe it is not an answer to your question, but why don't you help
> Postgres by yourself?

Thanx,

i dont think that the issue here is to help postgresql by myself.
I can always stick to 7.2.3, or use indexes that 7.3.1 will
acknowledge, like noonf_vcode_date on noon (v_code,report_date).
(unfortunately when i create the above noonf_vcode_date index, it is only
used until
the next vacuum analyze, hackers is this an issue too???),
but these options are not interesting from a postgresql perspective :)

> For this kind of queries it's better to drop index on report_date - your
> report period is one year and answer to this condition is 10% records (I
> suppose)

I cannot drop the index on the report_date since a lot of other queries
need it.

> It would be better to change 2 indexes on v_code and rotation into one
> index based on both fields.
> What kind of queries do you have? How many records returns each "where"
> condition? Use indexes on fields, on which condition result in smallest
> amount of rows.
>
> Regards,
> Tomasz Myrta
>

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Achilleus Mantzios
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