Re: COPY speedup

Il Thursday 13 December 2007 19:56:02 Tom Lane ha scritto:
> Reg Me Please <regmeplease(at)gmail(dot)com> writes:
> > In order to speed up the COPY ... FROM ... command, I've
> > disabled everything (primary key, not null, references, default and
> > indexes) in the table definition before doing the actual COPY.
> > Later I can restore them with ALTER TABLE ... and CREATE INDEX ...
> >
> > My question is: is all this necessary, or could I save some of them
> > (maybe just the DEFAULT) with no speed cost?
>
> Indexes and foreign key references are the only things that benefit
> from this treatment. DEFAULTs are irrelevant to a COPY, and simple
> constraints (NOT NULL and CHECK) are not any faster to verify later
> --- which makes dropping them slower, since you'll need an additional
> table scan to verify them when they're re-added.
>
> regards, tom lane

I'd suppose that foreign keys are to be "disabled" in order to speed things
up. Right?

--
Reg me, please!