Thread: Can i Force to postgrsql to use a certain index?

Hi every body

 it is possible to force to postgresql to use a certain index? I know that in mysql exits Force index (index_name) option for select queries
SELECT * FROM precalc FORCE INDEX (hladrb50101) ;

any of you have used this?

thanks

pau


--
Pau Marc Muñoz Torres

Laboratori de Biologia Computacional  
Institut de  Biotecnologia   i Biomedicina Vicent Villar                                    
Universitat Autonoma de Barcelona
E-08193 Bellaterra (Barcelona)
              
telèfon: 93 5812807
Email : paumarc.munoz@bioinf.uab.cat

Pau Marc Munoz Torres wrote:
> Hi every body
>
>  it is possible to force to postgresql to use a certain index? I know
> that in mysql exits Force index (index_name) option for select queries
> SELECT * FROM precalc FORCE INDEX (hladrb50101) ;
>
> any of you have used this?

No. PostgreSQL will not allow you to do that. Not to mention, a SELECT *
without a where clause will always scan the whole table so an Index
would be useless.

Joshua D. Drake

>
> thanks
>
> pau
>
>
> --
> Pau Marc Muñoz Torres
>
> Laboratori de Biologia Computacional
> Institut de  Biotecnologia   i Biomedicina Vicent
> Villar
> Universitat Autonoma de Barcelona
> E-08193 Bellaterra (Barcelona)
>
> telèfon: 93 5812807
> Email : paumarc.munoz@bioinf.uab.cat <mailto:paumarc.munoz@bioinf.uab.cat>