Ok so i'm working on triggers, and it tells me it(MySQL workbench 5.2) doesn't recognize this variable.
*Error Code: 1193. Unknown system variable error_msg_3*
I think it would be correct using it in a trigger, please help me
CREATE TRIGGER controlla_MaxCARDINALITA_INSERT
BEFORE INSERT ON SENTIERO__HA__TAPPA
FOR EACH ROW
BEGIN
DECLARE max_cardinalita INTEGER;
DECLARE error_msg_3 CONDITION FOR SQLSTATE '99003';
SELECT COUNT(*) into max_cardinalita
FROM SENTIERO__HA__TAPPA
WHERE IDsentiero=NEW.IDsentiero;
IF max_cardinalita>=10 THEN
SIGNAL error_msg_3;
SET error_msg_3='INSERT: Il sentiero ha già il massimo numero di tappe consentito';
END IF;
END$$
EDIT ::
I tried this, and it seems working
DECLARE msg VARCHAR(255);
set msg = concat('MyTriggerError: Trying to insert a negative value in trigger_test: ');
signal sqlstate '45000' set message_text = msg;
According to MySQL docs, the error #1193 occurs when you use wrong code for SQLSTATE.
Message: Unknown system variable %s
And, as you can see on the same page, the SQLSTATE 99003 is not defined.
Related
My code is:i am using mysql 5.6 and workbench 6.3CE
CREATE DEFINER=`root`#`windows7test-pc` PROCEDURE `p`(divisor INT)
BEGIN
Declare MESSAGE_TEXT varchar(200);
IF divisor = 0 THEN
BEGIN
DECLARE my_error CONDITION FOR SQLSTATE '45000';
SIGNAL my_error;
set MESSAGE_TEXT='error occured in if block';
END;
END IF;
END
when i apply this stored procedure then i get no error but when i run this by calling call p(0) statement then i get only system error message which is Error Code: 1644
Unhandled user-defined exception condition.but my question is that why the mysql server not generate my error message whic is MESSAGE_TEXT='error occured in if block'; ?
Use SIGNAL SQLSTATE:
CREATE PROCEDURE `p`(divisor INT)
BEGIN
Declare MESSAGE_TEXT varchar(200);
IF divisor = 0 THEN
BEGIN
SIGNAL SQLSTATE '45000'
set MESSAGE_TEXT='error occured in if block';
END;
END IF;
END
CALL `p`(0)
-- error occured in if block
SqlFiddleDemo
I'm trying to write a trigger for a table named classes_tbl where I basically want to check before update if the participants are at the maximum, if true - do not allow update, and raise error message.
As well as check if participants = 0 in case the the update table tries to decrease the number, it needs not to be possible to decrease below 0 - and again raise an error message in this case.
I'm not 100% accustomed to MySQL so I'm not sure what is missing or wrong. It would be nice If someone could give me a hint.
Here is my Create Trigger syntax:
DELIMITER //
CREATE TRIGGER MaxBelegt_TRGGR
BEFORE UPDATE ON classes_tbl
FOR EACH ROW
BEGIN
DECLARE
n_count NUMBER(3);
msg varchar(255);
SELECT maxParticipants
INTO n_count
FROM rooms_tbl
WHERE rid = :NEW.rid;
IF :OLD.participants = n_count THEN
set msg = concat('MyTriggerError: MaxParticipants for Room exceeded. On MaxBelegt_TRGGR -> belegtAnz : ', cast(OLD.participants as char));
signal sqlstate '45000' set message_text = msg;
END IF;
IF :NEW.participants < 0 THEN
set msg = concat('MyTriggerError: Participant number already 0. On MaxBelegt_TRGGR -> belegtAnz : ', cast(OLD.participants as char));
signal sqlstate '45000' set message_text = msg;
END IF;
END
//
DELIMITER;
Thank You!
BTW: I'm using mysql version : 5.6.24 .. just in case
I am programming the error handling in a MySQL stored procedure using SIGNAL. I want to parametrize the error message to make it more helpful. For example
IF vMyVariable IS NULL THEN
SIGNAL SQLSTATE VALUE '45006'
SET MESSAGE_TEXT = ('Found null variable in iteration' || vId);
END IF;
I tried to use concat() and didn't work.
See https://dev.mysql.com/doc/refman/5.5/en/signal.html
and in particular the section about simple_value_specification
Arbitrary expression can not be used when assigning attributes with SET, as in:
SIGNAL SQLSTATE VALUE '45006' SET MESSAGE_TEXT = <sorry, no arbitrary expressions here>;
However, a local variable is a simple_value_specification, so the following does work:
DECLARE my_message_text VARCHAR(64);
my_message_text := <anything you want>;
SIGNAL SQLSTATE VALUE '45006' SET MESSAGE_TEXT = my_message_text;
I am trying to setup a trigger so an insert does not occur if a condition is not met.
I thought the below was the way to do it but i am not sure
I am getting an error
/* SQL Error (1407): Bad SQLSTATE: '45000 ' */
Can anyone let me know why I am getting this error and the best way for me to prevent an insert if the condition is not met in mysql.
DELIMITER $$
SHOW WARNINGS$$
USE `warrington_central`$$
CREATE TRIGGER before_insert_image_comment_section_check
BEFORE INSERT ON image_comment FOR EACH ROW
BEGIN
DECLARE error_msg varchar(255);
IF New.section != (SELECT id from section where section = "image")
THEN SET error_msg = "Cannot insert a comment into this section as it is the wrong section type";
SIGNAL SQLSTATE '45000 'SET MESSAGE_TEXT = error_msg;
END IF;
END
$$
SHOW WARNINGS$$
SQLSTATE is required to be a a 5 character string unless previously declared using DECLARE ... CONDITION;
SIGNAL SQLSTATE '45000 'SET MESSAGE_TEXT = error_msg;
You're trying to set SQLSTATE to '45000 ' (note the space) which is 6 characters long. Fix the spacing and you should not see the message again (it is also reflected in your error message, but the space is a bit hard to see)
My proposed trigger:
#START TRIGGER
delimiter //
DECLARE msg VARCHAR(255);
CREATE TRIGGER passStandard_check BEFORE INSERT ON Module
FOR EACH ROW
BEGIN
IF NEW.passStandard < 0 || NEW.passStandard > 1 THEN
set msg = concat('Trigger Error: Pass Standard: ', cast(NEW.passStandard as char));
signal sqlstate '45000' set message_text = msg;
END
//
delimiter ;
#END TRIGGER
But I get the following error:
Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DECLARE msg VARCHAR(255); CREATE TRIGGER passStandard_check BEFORE INSERT ON Mod' at line 1
Adding in END IF does not make any difference.
passStandard is set to an INT NOT NULL.
Edit
I've moved the DECLARE statement after the BEGIN:
#START TRIGGER
delimiter //
CREATE TRIGGER passStandard_check BEFORE INSERT ON Module
FOR EACH ROW
BEGIN
DECLARE msg VARCHAR(255);
IF NEW.passStandard < 0 || NEW.passStandard > 1 THEN
set msg = concat('Trigger Error: Pass Standard: ', cast(NEW.passStandard as char));
signal sqlstate '45000' set message_text = msg;
END IF;
END
//
delimiter ;
#END TRIGGER
But I still get this error:
Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'sqlstate '45000' set message_text = msg; END IF; END' at line 7
You need to declare your variable "msg" inside your procedure and use END IF
#START TRIGGER
delimiter //
CREATE TRIGGER passStandard_check BEFORE INSERT ON Module
FOR EACH ROW
BEGIN
DECLARE msg VARCHAR(255); /* << PUT THIS HERE */
IF NEW.passStandard < 0 || NEW.passStandard > 1 THEN
set msg = concat('Trigger Error: Pass Standard: ', cast(NEW.passStandard as char));
signal sqlstate '45000' set message_text = msg;
END IF; /* << YOU WILL NEED THIS TOO (DONT FORGET THE SEMICOLON :D) */
END//
delimiter ;
#END TRIGGER
I noticed that I was getting MySQL warnings when adding triggers with IF/ELSE logic in them if I wasn't adding parentheses to the IF statements. Not sure why, but I added the brackets and the warnings went away. Try something like:
IF ((NEW.passStandard < 0) || (NEW.passStandard > 1)) THEN
set msg = concat('Trigger Error: Pass Standard: ', cast(NEW.passStandard as char));
signal sqlstate '45000' set message_text = msg;
END IF;
Try breaking it up to several queries. Or run it in phpmyadmin which handles semi colon separated multi queries.
Might be this:
DECLARE is permitted only inside a BEGIN ... END compound statement and must be at its start, before any other statements.
http://dev.mysql.com/doc/refman/5.0/en/declare.html
i got it working. pls find below the working code.
delimiter //
CREATE TRIGGER test_check1 BEFORE INSERT ON employee
FOR EACH ROW
BEGIN
DECLARE msg VARCHAR(255);
IF (NEW.sync_id = '0') THEN
SET NEW.name = 'Collect Money';
signal sqlstate '45000' set message_text = msg;
END IF;
END//
delimiter ;