Re: ISOLATION LEVEL SERIALIZABLE

On Tue, 26 Mar 2002, power2themacs wrote:

> >In table two you would not create a serial instead you would create an
> >INTEGER because serial is a counter and the values in table 2 may not be
> >in table 1.
> >
> >Use a transaction like as follows
> >
> >BEGIN;
> >INSERT INTO TABLE1 VALUES (Whatever values);
> >var = SELECT CURRVAL('sequence_name');
> >INSERT INTO TABLE2 VALUES (var,whatever else);
> >COMMIT;
> >
>
> But this is the race condition I am trying to avoid. Someone can
> insert before I get the currval and it will beincremented and this
> will result in invalid data. Right now, I'm doing exactly that but I

That will only happen if another insert occurs *in your session*.

Currval is defined to give the last value from your session, so whatever
happens in other sessions will not affect the value returned from currval.