SQL performance problems

Hi List,

I still have performance problems with this sql:

SELECT /*+ */
ftnfco00.estado_cliente ,
ftcofi00.grupo_faturamento ,
SUM( DECODE( ftcofi00.atual_fatura, '-', -(NVL(ftnfpr00.qtde_duzias,0)),
'+', NVL(ftnfpr00.qtde_duzias,0), 0) ) ,
SUM( DECODE( ftcofi00.atual_fatura, '-', -(NVL(ftnfpr00.vlr_liquido,0)), '+',
NVL(ftnfpr00.vlr_liquido,0), 0) ) ,
ftprod00.tipo_cadastro||ftprod00.codigo_produto ,
ftprod00.descricao_produto ,
DIVIDE( SUM( DECODE( ftcofi00.atual_fatura, '-', -(NVL(ftnfpr00.vlr_liquido,0)),
'+', NVL(ftnfpr00.vlr_liquido,0), 0)*ftnfpr00.margem_comercial ),
SUM( DECODE( ftcofi00.atual_fatura, '-',
-(NVL(ftnfpr00.vlr_liquido,0)), '+', NVL(ftnfpr00.vlr_liquido,0), 0)) ) ,
SUM( DECODE( ftcofi00.nf_prodgratis, 'S', NVL(ftnfpr00.qtde_duzias,0), 0 ) ) ,
SUM( DECODE( ftcofi00.nf_prodgratis, 'S', NVL(ftnfpr00.vlr_liquido,0), 0 ) )
FROM
ftprod00 ,
ftnfco00 ,
ftcgma00 ,
ftcgca00 ,
ftspro00 ,
ftclcr00 ,
gsames00 ,
ftcofi00 ,
ftrepr00 ,
gsesta00 ,
ftsupv00 ,
ftgrep00 ,
ftclgr00 ,
ftband00 ,
fttcli00 ,
ftredc00 ,
ftnfpr00
WHERE
ftnfco00.emp = 909 AND
ftnfpr00.fil IN ('101') AND
ftnfco00.situacao_nf = 'N' AND
TO_CHAR(ftnfco00.data_emissao,'YYYYMM') >= '200208' AND
TO_CHAR(ftnfco00.data_emissao,'YYYYMM') <= '200303' AND
ftcofi00.grupo_faturamento >= '01' AND
(ftcofi00.atual_fatura IN ('+','-') OR ftcofi00.nf_prodgratis = 'S') AND
ftcgma00.emp = ftprod00.emp AND
ftcgma00.fil = ftprod00.fil AND
ftcgma00.codigo = ftprod00.cla_marca AND
ftcgca00.emp = ftprod00.emp AND
ftcgca00.fil = ftprod00.fil AND
ftcgca00.codigo = ftprod00.cla_categoria AND
ftspro00.emp = ftprod00.emp AND
ftspro00.fil = ftprod00.fil AND
ftspro00.codigo = ftprod00.situacao AND
ftclcr00.emp = ftnfco00.emp AND
ftclcr00.fil = ftnfco00.empfil AND
ftclcr00.tipo_cadastro = ftnfco00.tipo_cad_clicre AND
ftclcr00.codigo = ftnfco00.cod_cliente AND
gsames00.ano_mes = TO_CHAR(ftnfco00.data_emissao,'YYYYMM') AND
ftcofi00.emp = ftnfco00.emp AND
ftcofi00.fil = ftnfco00.empfil AND
ftcofi00.codigo_fiscal = ftnfco00.cod_fiscal AND
ftrepr00.emp = ftnfco00.emp AND
ftrepr00.fil = ftnfco00.empfil AND
ftrepr00.codigo_repr = ftnfco00.cod_repres AND
gsesta00.estado_sigla = ftnfco00.estado_cliente AND
ftsupv00.emp = ftrepr00.emp AND
ftsupv00.fil = ftrepr00.fil AND
ftsupv00.codigo_supervisor = ftrepr00.codigo_supervisor AND
ftgrep00.emp = ftrepr00.emp AND
ftgrep00.fil = ftrepr00.fil AND
ftgrep00.codigo_grupo_rep = ftrepr00.codigo_grupo_rep AND
ftclgr00.emp = ftclcr00.emp AND
ftclgr00.fil = ftclcr00.fil AND
ftclgr00.codigo = ftclcr00.codigo_grupo_cliente AND
ftband00.emp = ftclcr00.emp AND
ftband00.fil = ftclcr00.fil AND
ftband00.codigo = ftclcr00.bandeira_cliente AND
fttcli00.emp = ftclcr00.emp AND
fttcli00.fil = ftclcr00.fil AND
fttcli00.cod_tipocliente = ftclcr00.codigo_tipo_cliente AND
ftredc00.emp = ftclcr00.emp AND
ftredc00.fil = ftclcr00.fil AND
ftredc00.tipo_contribuinte = ftclcr00.tipo_contribuinte AND
ftredc00.codigo_rede = ftclcr00.codigo_rede AND
gsesta00.estado_sigla = ftclcr00.emp_estado AND
ftnfco00.emp = ftnfpr00.emp AND
ftnfco00.fil = ftnfpr00.fil AND
ftnfco00.nota_fiscal = ftnfpr00.nota_fiscal AND
ftnfco00.serie = ftnfpr00.serie AND
ftnfco00.data_emissao = ftnfpr00.data_emissao AND
ftprod00.emp = ftnfpr00.emp AND
ftprod00.fil = ftnfpr00.empfil AND
ftprod00.tipo_cadastro = ftnfpr00.tipo_cad_promat AND
ftprod00.codigo_produto= ftnfpr00.cod_produto
GROUP BY
ftnfco00.estado_cliente ,
ftcofi00.grupo_faturamento ,
ftprod00.tipo_cadastro||ftprod00.codigo_produto ,
ftprod00.descricao_produto

I have created some oracle function in the database 'cuz I want the same
alication to use both Oracle or PostgreSQL without changing any source.

atached follow tha explain analyze for this query and my postgresql.conf.

I still searching a way to make it faster. I've tried to change a lot of
variables values like sort_mem, effective_cache_size, fsync, ...
I change the machine box from a Pentium III 1Ghz with 256 RAM to a P4 1.7 with
512 RAM DDR.
I don't know what else to do !

Atenciosamente,

Rhaoni Chiu Pereira
Sistêmica Computadores

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