I have a requirement where the status of the column changes from x to y.
I want to capture which process changed the value from x to y in a log table
and raise an exception to roll back the update using Oracle BEFORE UPDATE trigger
Is this possible using pragma autonomous_transaction ?
Please help.
It's possible. I'm assuming that you know how to identify the "process that changed the value" which I'm guessing is coming from some column in v$session or a user-defined context or some similar source.
You'd normally define a procedure
CREATE OR REPLACE PROCEDURE log_error( <<parameters>> )
AS
PRAGMA autonomous_transaction;
BEGIN
insert into log_table ...
commit;
END;
and then call that procedure from a trigger that throws an exception
CREATE OR REPLACE TRIGGER trg_no_x_to_y
BEFORE UPDATE ON table_name
FOR EACH ROW
BEGIN
IF( :old.column = x and :new.column = y )
THEN
log_error;
raise_application_error( -20001, 'Cannot change column from x to y' );
END IF;
END;
Related
This question already has answers here:
syntax Error in PostgreSQL when I try to create Trigger
(2 answers)
Closed last year.
I am getting a syntax error for my code which I can't understand why
am I missing something?
also, I read this I did not get my answer
syntax Error in PostgreSQL when I try to create Trigger
CREATE TRIGGER MyExampleName AFTER INSERT ON baskets
FOR EACH ROW BEGIN
UPDATE customers
SET customers.credit=customers.credit - NEW.amount
WHERE customers.id = NEW.customer_id;
END;
and tried it like this as well:
CREATE TRIGGER MyExampleName AFTER INSERT ON baskets
FOR EACH ROW AS $$ BEGIN
UPDATE customers
SET customers.credit=customers.credit - NEW.amount
WHERE customers.id = NEW.customer_id;
END;
$$ LANGUAGE plpgsql;
Error:
ERROR: syntax error at or near "BEGIN"
LINE 2: FOR EACH ROW BEGIN
^
SQL state: 42601
Character: 67
I'd say the first comment on your question pretty much covers it all. You cannot put the trigger code in the trigger body, you must first create a separate function and include the function call inside the trigger body.
This example comes directly from the Postgres docs:
-- 1. Create the function that does what you need
CREATE FUNCTION emp_stamp() RETURNS trigger AS $emp_stamp$
BEGIN
-- Check that empname and salary are given
IF NEW.empname IS NULL THEN
RAISE EXCEPTION 'empname cannot be null';
END IF;
IF NEW.salary IS NULL THEN
RAISE EXCEPTION '% cannot have null salary', NEW.empname;
END IF;
-- Who works for us when they must pay for it?
IF NEW.salary < 0 THEN
RAISE EXCEPTION '% cannot have a negative salary', NEW.empname;
END IF;
-- Remember who changed the payroll when
NEW.last_date := current_timestamp;
NEW.last_user := current_user;
RETURN NEW;
END;
$emp_stamp$ LANGUAGE plpgsql;
-- 2. Create the trigger with the 'EXECUTE FUNCTION function_name' part
-- replacing the actual function name from step 1.
CREATE TRIGGER emp_stamp BEFORE INSERT OR UPDATE ON emp
FOR EACH ROW EXECUTE FUNCTION emp_stamp();
I Have a following trigger, which updates but and rolling back automatically, I'm not finding what is the cause, kindly help.
FYI: updating table UDF_DATA has a foreign key reference to CCEX.CUSTOMER triggering table.
CREATE OR REPLACE TRIGGER TR_CUSTOMER_PM
AFTER INSERT OR UPDATE ON CCEX.CUSTOMER FOR EACH ROW
DECLARE
i_subscriber_id Number :=3080;
user_xcep EXCEPTION;
PRAGMA EXCEPTION_INIT( user_xcep, -20001 );
pragma autonomous_transaction;
i_syscode ccex.customer.cust_system_code%type;
BEGIN
IF :new.cust_account_number like 'TID%' THEN
i_syscode:= :new.cust_system_code;
update udf_data set value = 'Term'
where subscriber_id = i_subscriber_id
and cust_system_code = i_syscode
and entity_id = '1488_OTA'
and udf_id = '3994_OTA'
and name = 'Primary Manager';
END IF;
EXCEPTION
when others then
raise user_xcep;
END;
/
Since the trigger is in autonomous_transaction mode, it should close the transaction.
Please add commit just before the exception line.
I have a few things of code I need help debugging but I feel that if I can get one of them running i'll be able to get the rest(oh how i hope).
create or replace
trigger minimumwage
before insert or update on Employee
for each row
begin
if :new.Wage < 7.25
then raise_application_error('-20000,Pay is below Texas minimum wage!');
end if;
end;
/
I'm trying to do this on a table ran on my school's server through sqlplus if that helps.
When you're getting an error, it's always helpful to specify what error. There is a syntax error in the raise_application_error call in your trigger. That procedure takes two arguments, a number and a string. You are passing in a single argument that is one long string.
create or replace trigger minimumwage
before insert or update on Employee
for each row
begin
if :new.Wage < 7.25
then
raise_application_error(-20000,'Pay is below Texas minimum wage!');
end if;
end;
should be valid assuming there is a WAGE column in your EMPLOYEE table.
create or replace trigger deny_dec_pu before update of PU on ARTICLE
for each row
declare
erreur_pu exception;
begin
*insert into erreur values ('Operation de MAJ',sysdate);*
-- this intruction is never executec why ?
if (:new.pu < :old.pu) then
raise erreur_pu ;
end if;
exception
when erreur_pu then
Raise_application_error(-20100, 'rrrrrrrr', FALSE);
end;
/
I have a problem with trigger not working. Here is my trigger code
create or replace trigger "ZIVOTINJE_T2"
BEFORE
insert or update on "ZIVOTINJE"
for each row
begin
IF new.cijena>10 THEN
:new.cijena:=9.9
ELSEIF new.cijena<0 THEN
:new.cijena:=0.1
END IF;
end;
When I try to insert entity in table ZIVOTINJE, I get this
ORA-04098: trigger 'DENISS.ZIVOTINJE_T2' is invalid and failed re-validation
I can see three problems in the code of your trigger:
You need to refer to the new values of the row using :new (including the colon), not new.
To change values that are about to be inserted/updated, write :new.cijena := 9.9; instead of SET new.cijena=9.9. Note that (a) there is no SET keyword here; (b) the assignment operator is :=, not =; and (c) you need a semi-colon at the end of the line.
Use ELSIF instead of ELSEIF.
Finally, in SQL*Plus, you can use SHOW ERRORS TRIGGER "ZIVOTINJE_T2" to show the errors for this trigger.
try this.
CREATE OR REPLACE TRIGGER "ZIVOTINJE_T2"
BEFORE
insert or update on "ZIVOTINJE"
for each row
begin
IF :new.cijena = 10 THEN
:new.cijena := 9.9;
ELSE
IF :new.cijena < 0 THEN
:new.cijena := 0.1;
END IF;
end if;
end;
I'm trying to create a trigger for my table which automatically adds a published date based on when a certain flag is set to 'Y'
I don't have much experience with creating triggers but so far this is what i've got
create or replace
TRIGGER ADD_CREATE_DT
after UPDATE of approved ON articles
for each row
BEGIN
:new.create_dt := sysdate where approved = 'Y';
END;
I get this error when updating the column
trigger 'USER.ADD_CREATE_DT' is invalid and failed re-validation
Any ideas?
Thanks
Use the WHEN clause:
create or replace
TRIGGER ADD_CREATE_DT
after UPDATE of approved ON articles
for each row
when (new.approved = 'Y')
BEGIN
:new.create_dt := sysdate;
END;
Or use IF:
create or replace
TRIGGER ADD_CREATE_DT
after UPDATE of approved ON articles
for each row
BEGIN
if :new.approved = 'Y' then
:new.create_dt := sysdate;
end if;
END;
In this case, WHEN is more appropriate and efficient.
create or replace
TRIGGER ADD_CREATE_DT
after UPDATE of approved ON articles
for each row
BEGIN
IF :NEW.approved = 'Y' THEN
:new.create_dt := sysdate;
END IF;
END;
I don't know What version of Oracle do you use?
In Oracle 10g I got the following error:
ORA-04084: cannot change NEW values for this trigger type
04084. 00000 - "cannot change NEW values for this trigger type"
*Cause: New trigger variables can only be changed in before row
insert or update triggers.
*Action: Change the trigger type or remove the variable reference.
It does not allow to change the field on AFTER triggers.