Обсуждение: Set flag column on update if other columns change?

I've got a table where updates that actually change things need to
record in the row that the row has been modified.  I'm assuming that a
trigger function (OK to be plpgsql, performance isn't much of
an issue) is the best way to do this, but haven't done much
with trigger functions.  Can someone give me some pointers
on how this might be accomplished?  I have to check for
changes in a subset of the columns (e.g. ignore timestamps, etc.).

Thanks in advance!
Steve
-- 
Steve Wampler -- swampler@noao.edu
The gods that smiled on your birth are now laughing out loud.

> Steve Wampler <swampler@noao.edu> hat am 27. Mai 2014 um 18:00 geschrieben:
>
>
>
> I've got a table where updates that actually change things need to
> record in the row that the row has been modified.  I'm assuming that a
> trigger function (OK to be plpgsql, performance isn't much of
> an issue) is the best way to do this, but haven't done much
> with trigger functions.  Can someone give me some pointers
> on how this might be accomplished?  I have to check for
> changes in a subset of the columns (e.g. ignore timestamps, etc.).

Trigger BEFORE, compare NEW. with OLD.. Easy.

On 05/27/2014 09:21 AM, Andreas Kretschmer wrote:
>> Steve Wampler <swampler@noao.edu> hat am 27. Mai 2014 um 18:00 geschrieben:
>> I've got a table where updates that actually change things need to
>> record in the row that the row has been modified.  I'm assuming that a
>> trigger function (OK to be plpgsql, performance isn't much of
>> an issue) is the best way to do this, but haven't done much
>> with trigger functions.  Can someone give me some pointers
>> on how this might be accomplished?  I have to check for
>> changes in a subset of the columns (e.g. ignore timestamps, etc.).
>
> Trigger BEFORE, compare NEW. with OLD.. Easy.

Thanks!  I didn't know about OLD...


-- 
Steve Wampler -- swampler@noao.edu
The gods that smiled on your birth are now laughing out loud.