I have a trigger function I'm trying to have execute in Postgres.
It compiles and adds the trigger, however it does not insert the value into the table as I had hoped.
The function it uses looks like this:
CREATE OR REPLACE FUNCTION
calc_gnpDifference(n integer, o integer)
RETURNS NUMERIC AS $$
SELECT $1 ::numeric - $2::numeric AS gnpDifference;
$$ LANGUAGE SQL;
And the Trigger part:
CREATE OR REPLACE FUNCTION autoCalculate() RETURNS TRIGGER AS $$
BEGIN
IF NEW.gnp_old > NEW.gnp_old THEN
NEW.gnpDifference := calc_gnpDifference(NEW.gnp_old, NEW.gnp);
END IF;
RETURN NEW;
END;
$$ LANGUAGE plpgsql;
DROP TRIGGER insertDifference ON country;
CREATE TRIGGER insertDifference BEFORE INSERT ON country
FOR EACH ROW EXECUTE PROCEDURE autoCalculate();
However, when I insert data, the trigger does not update the gnpDifference field as I had hoped. Thoughts on why this might be happening?
Obviously this condition: IF NEW.gnp_old > NEW.gnp_old will never be true so the trigger will never have any effect.
Related
I have made the following query which is working perfect by itself but when i call it inside trigger function i got problem.
select insert_new_grade('title0', return3_6(0), return3_6(1), return3_6(2), s.code)
FROM "student" as s
where find_st(s.grade)>=5;
insert_new_grade is a function that inserts a new row in a table every time it's being called.
Here is the trigger :
CREATE OR REPLACE FUNCTION insert_d()
RETURNS TRIGGER AS $$
BEGIN
select insert_new_grade('title0', return3_6(0), return3_6(1), return3_6(2), s.code)
FROM "student" as s
where find_st(s.grade)>=5;
return new;
END;
$$ LANGUAGE plpgsql;
and here is the insert function :
CREATE OR REPLACE FUNCTION insert_new_grade(title0 character(100), prof0 character(11), prof1 character(11))
RETURNS VOID AS $$
BEGIN
INSERT INTO "d_table"(thes0, title, grade, prof, secProf)
VALUES (null, title0, null, prof0, prof1);
END
$$
LANGUAGE 'plpgsql';
Is there a way to make the query work inside the trigger function ? If i use perform instead of select the insert function does not have result. I've read about cursors but I'm new in postgresql and I don't know how to do it. Any help ?
i modifited your trigger function:
check your trigger function in conlose pgAdmin, is visible raise info text
CREATE OR REPLACE FUNCTION insert_d()
RETURNS TRIGGER AS $$
declare
rec record;
BEGIN
for rec in (select * from student s where find_st(s.grade)>=5) loop
raise info 'LOOP code = %',rec.code;
PERFORM insert_new_grade('title0', return3_6(0), return3_6(1), return3_6(2), rec.code);
end loop;
return new;
END;
$$ LANGUAGE plpgsql;
I am attempting to create a trigger which will delete rows when a certain where clause criteria is met but it throws out an error. What am I doing wrong?
CREATE TRIGGER unknowns
AFTER INSERT
ON "Amazon".salesdatapcr
FOR EACH ROW
EXECUTE PROCEDURE delete_my_rows();
CREATE OR REPLACE FUNCTION delete_my_rows()
RETURNS trigger AS
$BODY$
BEGIN
DELETE FROM "Amazon".salesdatapcr WHERE "Builder" = 'unknown';
RETURN NEW;
END;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
You must encapsulate your DELETE statement in a function, so the trigger will become:
CREATE TRIGGER unknowns
AFTER INSERT
ON "Amazon".salesdatapcr
FOR EACH ROW
EXECUTE PROCEDURE delete_my_rows();
So you must create a function as follow:
CREATE OR REPLACE FUNCTION delete_my_rows()
RETURNS trigger AS
$BODY$
BEGIN
DELETE FROM "Amazon".salesdatapcr WHERE "Builder" = 'unknown';
RETURN NEW;
END;
HERE you can find a brief guide on trigger creation
When a row is inserted or updated in a specific table (in this example it's the table called 'fpl'). How can I include the affected table and schema in the notification?
SQL as follows:
CREATE TRIGGER fpl_event
AFTER INSERT OR UPDATE ON fpl
FOR EACH ROW
EXECUTE PROCEDURE fpl_notify();
CREATE OR REPLACE FUNCTION fpl_notify()
RETURNS trigger AS $$
BEGIN
NOTIFY dbNotification, 'something got insereted in fpl!';
RETURN NULL;
END;
$$ LANGUAGE PLPGSQL;
Update:
CREATE OR REPLACE FUNCTION fpl_notify() RETURNS trigger
AS
$$
BEGIN
EXECUTE format('notify dbNotification, ''%s''', TG_TABLE_SCHEMA);
RETURN NULL;
END;
$$ LANGUAGE PLPGSQL;
read trigger special variables
I have two functions that return the good value. But when I call those functions inside of a trigger they always returns 0 instead of the good value.
The return type of those functions is real. The direct and dramatic consequence is that the trigger inserts wrong values in tables when it is called.
The function:
create or replace function get_remaining_hour(id_user_v integer,id_absence_v_type integer,id_year_v integer) returns real as
$BODY$
BEGIN
return (select sum(number_hour)
from remaining_absence_day
where id_user= $1
and id_absence_type=$2
and id_year=$3 );
END;
$BODY$
LANGUAGE 'plpgsql' ;
The trigger function (modified for testing!):
create OR REPLACE function update_absence() returns TRIGGER AS
$BODY$
DECLARE
old_number_hour real;
BEGIN
old_number_hour:=get_remaining_hour(3,2,8);
insert into debugging(col,val) values('old_number_hour', old_number_hour);
return null;
END;
$BODY$
LANGUAGE 'plpgsql' ;
The trigger definition:
drop trigger if exists update_absence on absence;
CREATE TRIGGER update_absence
after update of type,duration_hour,duration_day on absence
for each ROW
execute procedure update_absence();
The presented code should work.
It is particularly odd that you see 0 as result. If no matching row is found in remaining_absence_day, you would see NULL, not 0. But if you call the function with the same parameters in the same environment you should see the same result to begin with.
The remaining possible explanation I can think of: confusion with the schema search path. Like: you have a second instance of the function get_remaining_hour() or the table remaining_absence_day in a different schema. And you call the function with a different setting for search_path.
Did you run your comparison in the same session?
How does the search_path influence identifier resolution and the "current schema"
Or, since you work with an AFTER trigger: there might be other triggers on table absence that modify the table remaining_absence_day, which are fired before your trigger.
All other modifications I made are of cosmetic nature or minor simplifications.
CREATE OR REPLACE FUNCTION get_remaining_hour(id_user_v int
, id_absence_v_type int
, id_year_v int)
RETURNS real AS
$func$
BEGIN
RETURN (
SELECT sum(number_hour)
FROM remaining_absence_day -- referencing the right table? see search_path
WHERE id_user = $1
AND id_absence_type = $2
AND id_year = $3
);
END
$func$ LANGUAGE plpgsql STABLE; -- don't quote the language name
CREATE OR REPLACE FUNCTION update_absence()
RETURNS TRIGGER AS
$func$
BEGIN
INSERT INTO debugging(col, val)
VALUES('old_number_hour', get_remaining_hour(3,2,8)); -- hard coded only for testing?
RETURN null; -- only good for AFTER trigger
END
$func$ LANGUAGE plpgsql;
DROP TRIGGER IF EXISTS update_absence ON absence;
CREATE TRIGGER update_absence
AFTER UPDATE OF type, duration_hour, duration_day ON absence
FOR EACH ROW EXECUTE PROCEDURE update_absence();
I'm working on my first ever Trigger. When I'm doing an INSERT on table I want to conditionaly remove rows from other table.
Here is a trigger:
CREATE OR REPLACE FUNCTION clear_seen_by()
RETURNS trigger AS
$BODY$
BEGIN
IF (OLD.popup = '1') THEN
DELETE FROM news_seen_by;
END IF;
RETURN NULL;
END;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
Invoked by:
CREATE TRIGGER clear_seen_by
AFTER INSERT
ON news
FOR EACH STATEMENT
EXECUTE PROCEDURE clear_seen_by();
As an error I see that NEW or OLD (if I motify the trigger) is not declared/unknown. Where is the problem?
In an INSERT statement you do not have an OLD record defined.
You should use NEW.popup instead, and also declare the trigger to be FOR EACH ROW.
CREATE OR REPLACE FUNCTION clear_seen_by() RETURNS trigger AS
$BODY$
BEGIN
IF (NEW.popup = '1') THEN
DELETE FROM news_seen_by;
END IF;
RETURN NULL;
END;
$BODY$
LANGUAGE plpgsql VOLATILE COST 100;
CREATE TRIGGER
clear_seen_by
AFTER INSERT ON
news
FOR EACH ROW EXECUTE PROCEDURE
clear_seen_by();
You declare a trigger FOR EACH STATEMENT. Maybe you need FOR EACH ROW?
FOR EACH STATEMENT triggers do not have NEW and OLD.