How to create a Trigger in a google cloud sql instance Database

Question

I'm with a problem during creationg of a trigger in my database. I've a MySQL Second Generation instance with a database (name: test) in my google cloud sql.

Right now i have multiple tables in my database and im trying to create a trigger in one of that tables using:

CREATE TRIGGER date_overlap_insert_start_date
BEFORE INSERT ON driver_operation
FOR EACH ROW 
BEGIN
  if exists(
            select 1
            from driver_operation
            where nif = NEW.nif
            and (NEW.start_date > start_Date and NEW.start_date < end_Date)) then
               signal sqlstate '45000' SET MESSAGE_TEXT = 'Overlaps with existing data';
  end if;
END;

The error i get is this: 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 '' at line 10

Is there anyone who can help me on this? This trigger is to prevent overlap in date fields.

Answer 1

With respect to Google Cloud Platform, an important thing to do is to go to your instance configuration, ie "Edit Configuration" then go to "Flags" and ensure that "log_bin_trust_function_creators" is set to on. This will solve issues in GCP making triggers, as well as allow you to create triggers in MySQL Workbench CE 8.0 without it crashing.

Answer 2

I had this exact same issue today. It is simply due the cloud sql instance viewing each semi colon as the end of a statement, so I can only assume it tries to execute each time it encounters one.

Try creating your trigger with:

/*!50003 CREATE*/ /*!50003 TRIGGER date_overlap_insert_start_date
BEFORE INSERT ON driver_operation
FOR EACH ROW 
BEGIN
  if exists(
        select 1
        from driver_operation
        where nif = NEW.nif
        and (NEW.start_date > start_Date and NEW.start_date < end_Date)) 
then
           signal sqlstate '45000' SET MESSAGE_TEXT = 'Overlaps with 
existing data';
end if;
END */

edited to fix my syntax. Was missing a semi-colon.