Re: Tips for re-using function results within single insert

On Friday 20 Sep 2002 5:52 pm, Chris Gamache wrote:
> This would be nice to be able to do...
>
> insert into test_table (a,b) select random()::text as "myrandom",
>   encode("myrandom",'base64');

Well, I'd be tempted to write a wrapper function tagged as "iscachable" and
call it with a parameter of the current transaction-id (see docs on trigger
functions) or current time (the one from now() which doesn't change per
transaction). If this gives you grief, try a standard constant.

This means PG will cache results as long as the parameter doesn't change, in
this case for the duration of the transaction.

HTH

- Richard Huxton