Re: Update performance ... is 200, 000 updates per hour what I should expect?

Erik Norvelle <erik(at)norvelle(dot)net> writes:
> update indethom
> set query_counter =3D nextval('s2.query_counter_seq'), -- Just=
> =20=20
> for keeping track of how fast the query is running
> sectref =3D (select clavis from s2.sectiones where
> s2.sectiones.nomeoper =3D indethom.nomeoper
> and s2.sectiones.refere1a =3D indethom.refere1a and=20=20
> s2.sectiones.refere1b =3D indethom.refere1b
> and s2.sectiones.refere2a =3D indethom.refere2a and=20=20
> s2.sectiones.refere2b =3D indethom.refere2b
> and s2.sectiones.refere3a =3D indethom.refere3a and=20=20
> s2.sectiones.refere3b =3D indethom.refere3b
> and s2.sectiones.refere4a =3D indethom.refere4a and=20=20
> s2.sectiones.refere4b =3D indethom.refere4b);

This is effectively forcing a nestloop-with-inner-indexscan join. You
might be better off with

update indethom
set query_counter = nextval('s2.query_counter_seq'),
sectref = sectiones.clavis
from s2.sectiones
where
s2.sectiones.nomeoper = indethom.nomeoper
and s2.sectiones.refere1a = indethom.refere1a and
s2.sectiones.refere1b = indethom.refere1b
and s2.sectiones.refere2a = indethom.refere2a and
s2.sectiones.refere2b = indethom.refere2b
and s2.sectiones.refere3a = indethom.refere3a and
s2.sectiones.refere3b = indethom.refere3b
and s2.sectiones.refere4a = indethom.refere4a and
s2.sectiones.refere4b = indethom.refere4b;

regards, tom lane