From: Denis Zaitsev <zzz@anda.ru>
To: pgsql-sql@postgresql.org
Subject: Re: Very strange 'now' behaviour in nested triggers.
Date: Sun, 27 Jul 2003 02:01:04 +0600
Message-ID: <20030727020104.A19865@natasha.ward.six> (raw)
References: <20030726193947.B1636@natasha.ward.six>
<9412.1059229904@sss.pgh.pa.us>
On Sat, Jul 26, 2003 at 10:31:44AM -0400, Tom Lane wrote:
> Denis Zaitsev <zzz@anda.ru> writes:
> > create table xxx (
> > s text,
> > t timestamp
> > default 'now'
> > );
>
> That's a dangerous way to define the default --- 'now' is taken as a
> literal of type timestamp, which means it will be reduced to a timestamp
> constant as soon as a statement that requires the default is planned.
> You lose in plpgsql because of plan caching, but you'd also lose if you
> tried to PREPARE the insert command. Example:
Aaa... So, the INSERT inside a trigger will use the 'now' for the
time this trigger is compiled (i.e. called first time)? Do I
understand right? And the only outer trigger uses the right 'now' as
its value goes from the top-level INSERT...
Thank you very much.
By the way, do you think this method with nested triggers has some
'moral weakness' vs. just cycling left-to-right on the comma-separated
string in the 'do instead' rule for some view of xxx?
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To: pgsql-sql@postgresql.org
Cc: zzz@anda.ru
Subject: Re: Very strange 'now' behaviour in nested triggers.
In-Reply-To: <20030727020104.A19865@natasha.ward.six>
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