Re: why does plperl cache functions using just a bool for is_trigger
From:
Alex Hunsaker <badalex(at)gmail(dot)com>
To:
Hannu Krosing <hannu(at)2ndquadrant(dot)com>
Cc:
Jan Urbański <wulczer(at)wulczer(dot)org>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Andrew Dunstan <andrew(at)dunslane(dot)net>, Postgres - Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject:
Re: why does plperl cache functions using just a bool for is_trigger
On Thu, Nov 4, 2010 at 13:43, Hannu Krosing <hannu(at)2ndquadrant(dot)com> wrote:
> So your plan was to have some savepoint before each execute ?
>
> How would one rollback the latest transaction ?
It is always rolled back. Its how plperl works today:
create or replace function foo() returns int as $$
eval {
spi_exec_query('create table uniq (num int primary key');
spi_exec_query('insert into uniq (num) values (1), (1);', 1);
};
if($@) {
# do something ... $@ == "duplicate key value violates unique
constraint "uniq_pkey" at line 2."
warn $@;
}
# oh well do something else
# note the transaction is _not_ aborted
spi_exec_query('select 1;', 1);
return 1;
$$ language plperl;
=# begin;
=# select foo();
=# select 1;
=# commit;
It does not matter if you use eval or not, its always in a sub transaction.
> I see. "exception when unique violation" in plpgsql does automatic
> rollback to block start (matching BEGIN) so I assumed that your
> try/except sample is designed to do something similar
Basically, minus the rollback to start. Its per query.
