Re: Deleting large amount of data.

Thanks for ask my post, Mr. Szabo.

Thanks for worry about my performance problems, but they are natural for
my database, once my hardware isn't a Ferrari and my table has more than 2
milion of touples and it's related with a lot of other very high populated
tables. I realized I can keep no longer than 6 mounths of data in these
tables, so I would like to remove older data every night. I didn't write any
code yet and I can't start testing the best way in my databases, so I'm
posting here to get some advices. I'm worried about performance problems
that could raise when a start removing 12000 touples in a single transaction
once I don't know how PostgreSQL works internally. Can a single transaction
deal with so many data without problem or overloading transaction buffers
(or something like that) or do I need to split deletion process in smaller
sets of data?

My main table wich has more than 2milion of touples :
CREATE TABLE cham_chamada (
cod_bxs integer NOT NULL,
chave integer NOT NULL,
identificacao integer NOT NULL,
dt_inicial timestamp NOT NULL,
indicadora integer,
cod_categoria integer,
identidadea varchar(20),
dt_final timestamp ,
juntor integer,
indicadorb integer,
identidadeb varchar(20),
flg_chamada char(1),
flg_liberacao char(1),
temp_total integer,
ddd smallint,
cod_liberjuntor integer,
cod_resultcham integer,
cod_fds integer,
cifra_origem integer,
csp char(2),
conta integer,
ramal varchar(20),
ultimo_ramal varchar(20),
CONSTRAINT XPKcham_chamada PRIMARY KEY (dt_inicial, cod_bxs, chave,
identificacao)

)
;

CREATE INDEX XIE1cham_chamada ON cham_chamada
(
dt_final ,
identidadea
);

CREATE INDEX XIE2cham_chamada ON cham_chamada
(
dt_final ,
flg_chamada
);