Re: Create Rule

Hello !

I would use a rule to store in each modified records the name of the user and the date of modification.
I try :

CREATE RULE shoe_mod AS ON UPDATE TO shoe_data
DO INSTEAD UPDATE shoe_data
SET shoename = NEW.shoename,
sh_avail = NEW.sh_avail,
slcolor = NEW.slcolor,
slminlen = NEW.slminlen,
slmaxlen = NEW.slmaxlen,
slunit = NEW.slunit,
shuser = current_user,
shdatmod = current_date
WHERE shoename = OLD.shoename ;

but I obtain an infinite loop ...
How can I do that.

Best regards.

Luc ROLLAND

On Tue, Feb 17, 2004 at 09:01:51PM +0100, Luc ROLLAND wrote:
> Hello !
>
> I would use a rule to store in each modified records the name of the user and the date of modification.
> I try :
>
> CREATE RULE shoe_mod AS ON UPDATE TO shoe_data
> DO INSTEAD UPDATE shoe_data
> SET shoename = NEW.shoename,
> sh_avail = NEW.sh_avail,
> slcolor = NEW.slcolor,
> slminlen = NEW.slminlen,
> slmaxlen = NEW.slmaxlen,
> slunit = NEW.slunit,
> shuser = current_user,
> shdatmod = current_date
> WHERE shoename = OLD.shoename ;
>
> but I obtain an infinite loop ...
> How can I do that.

Hi Luc,

Your rule specifies to update the table, and updating the table
triggers the rule, which specifies to update the table... ad
infinitum.

Try creating the rule on a view instead, then updating the view:

CREATE RULE shoe_data_v AS SELECT * FROM shoe_data;
CREATE RULE shoe_v_mod AS ON UPDATE TO shoe_data_v
DO INSTEAD UPDATE shoe_data
...

HTH,
Jeremy

okay, its a novice list so I'll take a crack at this one.

I couldn't find create rule as ... select .... in the documentation, only rules for insert,update,delete.
Using it says ERROR: parser: parse error at or near "*" at character 43
(that;s the * for the select)

I think the problem comes from bastardizing the documentation. You should be doing this on a view, and then updating the real table. It should be "AS ON UPDATE TO shoe_data_view DO INSTEAD UPDATE real_shoe_data_table. The link in the doc is
http://www.sirfsup.com/sql_servers/postgresql/pg_docs/rules-update.html
half-way down the page.

On Tue, Feb 17, 2004 at 01:14:15PM -0800, Jeremy Semeiks wrote:
> On Tue, Feb 17, 2004 at 09:01:51PM +0100, Luc ROLLAND wrote:
> > Hello !
> >
> > I would use a rule to store in each modified records the name of the user and the date of modification.
> > I try :
> >
> > CREATE RULE shoe_mod AS ON UPDATE TO shoe_data
> > DO INSTEAD UPDATE shoe_data
> > SET shoename = NEW.shoename,
> > sh_avail = NEW.sh_avail,
> > slcolor = NEW.slcolor,
> > slminlen = NEW.slminlen,
> > slmaxlen = NEW.slmaxlen,
> > slunit = NEW.slunit,
> > shuser = current_user,
> > shdatmod = current_date
> > WHERE shoename = OLD.shoename ;
> >
> > but I obtain an infinite loop ...
> > How can I do that.
>
> Hi Luc,
>
> Your rule specifies to update the table, and updating the table
> triggers the rule, which specifies to update the table... ad
> infinitum.
>
> Try creating the rule on a view instead, then updating the view:
>
> CREATE RULE shoe_data_v AS SELECT * FROM shoe_data;
> CREATE RULE shoe_v_mod AS ON UPDATE TO shoe_data_v
> DO INSTEAD UPDATE shoe_data
> ...
>
> HTH,
> Jeremy
>
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--
joe speigle
www.sirfsup.com