I am trying to implement the following trigger but I am getting a MySQL syntax error. The idea is that after each time the table is updated I want to set the updated 'valid' field to 0 if the 'banned' field has been changed to 1. Also is the logic below correct?
Create Trigger `customers` Before Update on `customers` for each row BEGIN
set new.valid = 0 WHERE new.banned = 1;
END;
Yes the trigger should be something as
delimiter //
Create Trigger `customers_update`
Before Update on `customers`
for each row
BEGIN
IF new.banned = 1
THEN set new.valid = 0 ;
END IF ;
END;//
As you can see I have used delimiter in the trigger which is needed for the trigger. There is a nice explanation of this here What does DELIMITER // do in a Trigger?
Related
I am trying to update a column ( called DateModified ) before update happens on the table row.
so here is my trigger:
CREATE TRIGGER `date_mod_category` BEFORE UPDATE ON `categories`
FOR EACH ROW BEGIN
SET new.DateModified = NOW();
END
BUT I GET THIS DAMN ERROR WHICH I JUST CANNOT FIGURE OUT WHY:
Use DELIMITER
DELIMITER //
CREATE TRIGGER `date_mod_category` BEFORE UPDATE ON `categories`
FOR EACH ROW
BEGIN
SET new.DateModified = NOW();
END //
DELIMITER ;
I am first time using trigger concept in my MYSQL workbench like below query,
First I created people table by using below query,
CREATE TABLE people (age INT, name varchar(150));
Then I used below query for trigger
DELIMITER
CREATE TRIGGER agecheck BEFORE INSERT ON raptor1_5.people FOR EACH ROW IF NEW.age < 0 THEN SET NEW.age = 0; END IF;
DELIMITER ;
But agecheck trigger not creating to people table. Its does not show any error message when I run this query.
Here is my table images,
Updated : based on the answer
Try with this.
USE `raptor1_5`;
DELIMITER $$
DROP TRIGGER IF EXISTS raptor1_5.agecheck$$
USE `raptor1_5`$$
CREATE TRIGGER agecheck BEFORE INSERT ON people
FOR EACH ROW
BEGIN
IF NEW.age < 0 THEN
SET NEW.age = 0;
END IF;
END$$
DELIMITER ;
The standard trigger syntax should be as
DELIMITER //
CREATE TRIGGER agecheck BEFORE INSERT ON raptor1_5.people
FOR EACH ROW
BEGIN
IF NEW.age < 0 THEN
SET NEW.age = 0;
END IF;
END;//
DELIMITER ;
The above is when you run on mysql cli, however in phpmyadmin or workbench check if you have an option to set the delimiter if yes choose that and remove the delimiter part from the above.
I created a simple trigger as below:
CREATE TRIGGER `trigger_update_rche_prep` BEFORE UPDATE ON `rche_prep`
FOR EACH ROW
SET NEW.case_number = 'ABC';
Which is working, when I want to add the BEGIN...END syntax to it, like below:
CREATE TRIGGER `trigger_update_rche_prep` BEFORE UPDATE ON `rche_prep`
FOR EACH ROW
BEGIN
SET NEW.case_number = 'ABC';
END;
It fails, I have no idea why this will happen, can anyone help?
Try this:
DELIMITER //
CREATE TRIGGER `trigger_update_rche_prep` BEFORE UPDATE ON `rche_prep`
FOR EACH ROW
BEGIN
SET NEW.case_number = 'ABC';
END;//
DELIMITER ;
The default initial value of one column in my database is the same as the row's auto-incremented id. I'm trying to use triggers to set it.
CREATE TRIGGER `default_order_value`
AFTER INSERT ON `clusters`
FOR EACH ROW
BEGIN
UPDATE `clusters` SET `order` = NEW.id WHERE `id` = NEW.id;
END
But this keeps throwing a syntax error
#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 '' at line 5
I've tried all sorts of permutations of this with no luck. Can anyone see what I'm doing wrong?
As zerkms said, you need to change the delimeter. But since you only use 1 line of code, you don't need the BEGIN and END. And that way, you don't need to change the delimiter either
CREATE TRIGGER `default_order_value`
AFTER INSERT ON `clusters`
FOR EACH ROW
UPDATE `clusters` SET `order` = NEW.id WHERE `id` = NEW.id;
Since you are getting an error you cannot update the row, I suggest the following:
Do NOT perform the update query at all. On default the order value = the ID value. So when the order value changes, you can update it properly.
If you are requesting the data with php, do something like this:
$order = $row['order'];
if ($order == '')
$order = $row['id'];
After you need it updating, you've got the correct value.
I don't think you can do that. An AFTER INSERT trigger cannot modify the same table, neither by issuing an UPDATE nor by something like this:
CREATE TRIGGER `default_order_value`
AFTER INSERT ON `clusters`
FOR EACH ROW
SET NEW.`order` = NEW.id ;
which results in this error:
> Error Code: 1362. Updating of NEW row is not allowed in after trigger
You can't either use a BEFORE INSERT trigger because then the NEW.id is not known (if you modify the above, the order column will get 0 value after the Insert.
What you can do, is use a transaction:
START TRANSACTION ;
INSERT INTO clusters (id)
VALUES (NULL);
UPDATE clusters
SET `order` = id
WHERE id = LAST_INSERT_ID();
COMMIT ;
You get the error because mysql treats ; in line 5 as the end of your trigger declaration, which obviously leads to the syntax error.
So you need to redefine delimiter before you specify the trigger body:
delimiter |
CREATE TRIGGER `default_order_value`
AFTER INSERT ON `clusters`
FOR EACH ROW
BEGIN
UPDATE `clusters` SET `order` = NEW.id WHERE `id` = NEW.id;
END;
|
delimiter ;
You can create just BEFORE INSERT TRIGGER, it's works like this:
CREATE TRIGGER `default_order_value`
BeFORE INSERT ON `clusters`
FOR EACH ROW
BEGIN
SET NEW.`order` = NEW.id ;
END
same as below we are using
DELIMITER $$
USE `e_store`$$
DROP TRIGGER /*!50032 IF EXISTS */ `Test`$$
CREATE
/*!50017 DEFINER = 'root'#'%' */
TRIGGER `Test` BEFORE INSERT ON `categories`
FOR EACH ROW
BEGIN
DECLARE vtype VARCHAR(250) DEFAULT NULL;
SET vtype = NEW.name;
IF (NEW.MDNAME IS NULL)
THEN
-- SET NEW.MDNAME = 'NA';
SET NEW.MDNAME=MD5(NEW.name);
END IF;
END;
$$
DELIMITER ;
This worked for me:
CREATE TRIGGER `update_table_2`
AFTER UPDATE ON `table_1`
FOR EACH ROW
UPDATE table2
JOIN table_1
SET table_2.the_column = NEW.the_column
WHERE table_2.auto_increment_field = OLD.auto_increment_field
I hav a table with several fields. One field is "date_assigned" and the other is "assigned". "date_assigned" has a datatype of timestamp and can be null. "assigned" has a datatype of tinyint and the values are either 0 (default; 'not assigned') or 1 ('assigned').
I would like to create a trigger that would automatically update the "assigned" value to 1 when "date_assigned" is updated with a value (is not null).
I've used triggers before, but have not used them in conjunction with checking if a value is null. I'm unclear on the syntax, so any help would be appreciated. So far, I've tried:
DELIMITER $$
CREATE
TRIGGER `<database>`.`<trigger_name>` AFTER UPDATE
ON `<database>`.`<table>`
FOR EACH ROW BEGIN
IF(NEW.date_assigned IS NOT NULL) THEN
UPDATE <table> SET assigned = '1';
END$$
DELIMITER ;
I just get Error Code: 1064. I looked upo the code, and it appears that it's a syntax error. So what syntax mistake am I making, and is this even the correct 'grammar'?
Try putting BEGIN in a new line as follows.
DELIMITER $$
CREATE
TRIGGER `<database>`.`<trigger_name>` AFTER UPDATE
ON `<database>`.`<table>`
FOR EACH ROW
BEGIN
IF(NEW.date_assigned IS NOT NULL) THEN
UPDATE <table> SET assigned = '1';
END; //Change here also.
$$
DELIMITER ;
This is because of default delimiter in MySQL set to ;. So, the first line should look like DELIMITER $$;
DELIMITER $$;
CREATE TRIGGER `<database>`.`<trigger_name>`
AFTER UPDATE ON `<database>`.`<table>`
FOR EACH ROW BEGIN
IF(NEW.date_assigned IS NOT NULL) THEN
UPDATE <table> SET assigned = '1';
END$$
DELIMITER ;