Its actually something like the trigger should start a C function after insert and the C function has the ECPG code for some more inserts.
Its similar to the way we dynamically load a shared library while executing a stored procedure, as in , executing a fucntion in C file using stored procedure/ function.
Harpreet
On 8/16/06, Harpreet Dhaliwal <harpreet.dhaliwal01@xxxxxxxxx> wrote:
I got your point.however, my requirement is something like this.The trigger shold start another function (a stored procedure) after any event is fired.how do I accomplish this goal?Harpreet
On 8/16/06, Michael Fuhr <mike@xxxxxxxx> wrote:On Wed, Aug 16, 2006 at 01:35:47AM -0400, Harpreet Dhaliwal wrote:
> I'm trying to create a trigger with the following definition:
>
> CREATE TRIGGER insert_price_change AFTER INSERT OR DELETE OR UPDATE ON
> raw_email
> FOR EACH ROW EXECUTE PROCEDURE add_one(1);
>
> Procedure / Function add_one has the following definition
>
> CREATE FUNCTION add_one(integer) RETURNS integer
> AS '/usr/local/pgsql/jsb/add_one', 'add_one'
> LANGUAGE C STRICT;
>
> function add_one is running fine.
>
> When I try to create the trigger insert_price_change, it throws me the
> follwoing error:
>
> ERROR: function add_one() does not exist
Trigger functions must return type "trigger" and they must be
declared with no arguments. You can pass an argument as in your
CREATE TRIGGER statement but a trigger function receives its arguments
differently than an ordinary function. See the Triggers chapter
in the documentation, especially "Writing Trigger Functions in C":
http://www.postgresql.org/docs/8.1/interactive/triggers.html
Unless you need to use C I'd suggest using PL/pgSQL. Even if you
do need to use C I'd recommend practicing with PL/pgSQL to learn
the basics with a simpler language.
http://www.postgresql.org/docs/8.1/interactive/plpgsql-trigger.html
--
Michael Fuhr
