Thread: planner doesn't use multicolumn index

> We've a table with about 8 million rows, and we need to get rows by the
> value of two of its fields( the type of the fields are int2 and int4,
> the where condition is v.g. partido=99 and partida=123). We created a
> multicolumn index on that fields but the planner doesn't use it, it
> still use a seqscan. That fields are primary key of the table and we
> clusterded the table based on that index, but it still doesn't work. We
> also set the enviroment variable enable_seqscan to false and nathing
> happends. The only way the planner use it is in querys that order by the
> expression of the index.
> Any idea?
> thanks.
> Adrián

where partido=99::int2 and partida=123;

Regards,
Tomasz Myrta

Adrian Demaestri wrote:

> We've a table with about 8 million rows, and we need to get rows by the value
 >of two of its fields( the type of the fields are int2 and int4,
>the where condition is v.g. partido=99 and partida=123). We created a
 >multicolumn index on that fields but the planner doesn't use it, it still use
 >a seqscan. That fields are primary key of the table and we clusterded the table
 >based on that index, but it still doesn't work. We also set the enviroment
 > variable enable_seqscan to false and nathing happends. The only way the
 >planner use it is in querys that order by the expression of the index.

Use partido=99::int2 and partida=123::int4

Match the data types basically..

  Shridhar

On Wed, 8 Oct 2003 09:08:59 -0500 (CDT), Adrian Demaestri
<ademaestri@yahoo.com> wrote:
>the type of the fields are int2 and
>int4, the where condition is v.g. partido=99 and partida=123).

Write your search condition as

    WHERE partido=99::int2 and partida=123

Servus
 Manfred