Re: [SQL] Update and trigger

am Tue, dem 10.06.2008, um 18:45:51 -0700 mailte Medi Montaseri folgendes:
> Hi,
>
> I need to increament a counter such as myTable.Counter of type integer
> everytime myTable.status a boolean column is updated. Can you help me complete
> this...
>
> create trigger counter_trigger after update on myTable.counter
> execute procedure 'BEGIN statement; statement; statement END'

much simpler, use a RULE instead a TRIGGER like my example:

Suppose, i have a table called foo, it contains now:

test=# select * from foo;
i
---
1
2
(2 rows)

I create a sequence and a RULE:

test=*# create sequence foo_counter;
CREATE SEQUENCE
test=*# create or replace rule foo_update as on update to foo do also select nextval('foo_counter');
CREATE RULE

And now i do a update on foo:

test=*# update foo set i=2;
nextval
---------
1
(1 row)

test=*# update foo set i=3;
nextval
---------
2
(1 row)

test=*# select currval('foo_counter');
currval
---------
2
(1 row)

Andreas
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Andreas Kretschmer
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