Can anyone explain me what below code actually do, I have this on my mysqlDB.sql exported file
DROP TRIGGER IF EXISTS `alertupdateevent`;
DELIMITER $$
CREATE TRIGGER `alertupdateevent` AFTER INSERT ON `RECOG`
FOR EACH ROW BEGIN
INSERT INTO `mydb`.`ALERTUPDATES` (`FIRSTNAME`, `LASTNAME`, `CAMNAME`, `TIMESTAMP`, `RESERVE1`, `ALERTTYPE`, `IMGURL`) VALUES (NEW.FIRSTNAME, NEW.LASTNAME, NEW.DOB, NEW.TIMESTAMP, NEW.FACEID, 'RECOG' , NEW.FACEURL);
END
$$
DELIMITER ;
Currently I dealing a project which is not developed by me, and I am not well familiarized with mysql.
The problem I am facing is I have two table in DB like RECOG and ALERTUPDATES and I need to insert data to both of these table(same data), and I can see only one php which insert data to the table `RECOG'.
So my question does the above piece of code insert data automatically to table ALERTUPDATES when data insert on RECOG table by php.
Try this..
CREATE TRIGGER trigger_name
BEFORE INSERT
ON table_name FOR EACH ROW
BEGIN
-- variable declarations
-- trigger code
END;
Parameters or Arguments
trigger_name
The name of the trigger to create.
BEFORE INSERT
It indicates that the trigger will fire before the INSERT operation is executed.
table_name
The name of the table that the trigger is created on.
RESTRICTIONS
You can not create a BEFORE trigger on a view.
You can update the NEW values.
You can not update the OLD values.
Example:
DELIMITER //
CREATE TRIGGER contacts_before_insert
BEFORE INSERT
ON contacts FOR EACH ROW
BEGIN
DECLARE vUser varchar(50);
-- Find username of person performing INSERT into table
SELECT USER() INTO vUser;
-- Update create_date field to current system date
SET NEW.created_date = SYSDATE();
-- Update created_by field to the username of the person performing the INSERT
SET NEW.created_by = vUser;
END; //
DELIMITER ;
Ref:http://www.techonthenet.com/mysql/triggers/before_insert.php
Yes, you are correct. Trigger are used to INSERT UPDATE on some TABLE based on action perform on some TABLE actions like insert, update or delete. Refer MySQL triggers