Re: Update and trigger - Mailing list pgsql-sql

Thanks...but a difference seems to be that the rule is not specific to update on a particular col but any col of a row
gettingupdated...<br /><br />Thanks<br /><br /><div class="gmail_quote">On Tue, Jun 10, 2008 at 10:21 PM, A. Kretschmer
<<ahref="mailto:andreas.kretschmer@schollglas.com">andreas.kretschmer@schollglas.com</a>> wrote:<br /><blockquote
class="gmail_quote"style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">am
 Tue,dem 10.06.2008, um 18:45:51 -0700 mailte Medi Montaseri folgendes:<br /><div class="Ih2E3d">> Hi,<br /> ><br
/>> I need to increament a counter such as myTable.Counter of type integer<br /> > everytime myTable.status a
booleancolumn is updated. Can you help me complete<br /> > this...<br /> ><br /> > create trigger
counter_triggerafter update on myTable.counter<br /> > execute procedure 'BEGIN statement; statement; statement
END'<br/><br /></div>much simpler, use a RULE instead a TRIGGER like my example:<br /><br /> Suppose, i have a table
calledfoo, it contains now:<br /><br /> test=# select * from foo;<br />  i<br /> ---<br />  1<br />  2<br /> (2
rows)<br/><br /><br /> I create a sequence and a RULE:<br /><br /> test=*# create sequence foo_counter;<br /> CREATE
SEQUENCE<br/> test=*# create or replace rule foo_update as on update to foo do also select nextval('foo_counter');<br
/>CREATE RULE<br /><br /><br /> And now i do a update on foo:<br /><br /><br /> test=*# update foo set i=2;<br />
 nextval<br/> ---------<br />       1<br /> (1 row)<br /><br /> test=*# update foo set i=3;<br />  nextval<br />
---------<br/>       2<br /> (1 row)<br /><br /><br /> test=*# select currval('foo_counter');<br />  currval<br />
---------<br/>       2<br /> (1 row)<br /><br /><br /><br /> Andreas<br /> --<br /> Andreas Kretschmer<br /> Kontakt:
 Heynitz:035242/47150,   D1: 0160/7141639 (mehr: -> Header)<br /> GnuPG-ID:   0x3FFF606C, privat 0x7F4584DA   <a
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