RES: Improving SQL performance

Yes, I do have an index on tt_log.codcep.

Indexes I´ve on both tables:

tt_end
Indexes:
    "pk_end" PRIMARY KEY, btree (filcli, codcli, codfil, numend)
    "ak_end_numdoc" UNIQUE, btree (numdoc)
    "i_fk_end_darc" btree (codarc, tiparc)
    "i_fk_end_dend" btree (tipend)
    "i_fk_end_dfil" btree (codfil)
    "i_fk_end_dreg" btree (regiao)
    "i_fk_end_mun" btree (codcid)
tt_log
Indexes:
    "i_fk_log_bai" btree (codbai)
    "i_lc_log_codcep" btree (codcep)

Any clue?

Thanks!

Reimer


> -----Mensagem original-----
> De: Tom Lane [mailto:tgl@sss.pgh.pa.us]
> Enviada em: quinta-feira, 11 de janeiro de 2007 16:31
> Para: carlos.reimer@opendb.com.br
> Cc: pgsql-performance@postgresql.org
> Assunto: Re: [PERFORM] Improving SQL performance
>
>
> "Carlos H. Reimer" <carlos.reimer@opendb.com.br> writes:
> > I know that the problem with the following SQL is the "LOG.CODCEP =
> > ENDE.CODCEP||CODLOG" condition, but what can I
> > do to improve the performance?
>
> Seems the problem is not using an index for tt_log.  Do you have an
> index on tt_log.codcep?  If so, maybe you need to cast the result of
> the concatenation to char(8) to get it to use the index.
>
>             regards, tom lane
>
>