Question

I’m having some problems with mySQL triggers.

I have this working:

CREATE TRIGGER `insert_trigger` AFTER INSERT ON `table`
FOR EACH ROW
BEGIN
IF (SELECT COUNT(*) FROM `table` WHERE userID = NEW.userID AND IP = new.IP) = 0 THEN
    IF (SELECT COUNT(*) FROM `table` WHERE userID = NEW.userID) = 0 THEN
        INSERT INTO `table2` VALUES(NEW.userID, (SELECT (COUNT(*)+1) FROM `table` WHERE userID = NEW.userID) ); 
    ELSE 
        UPDATE `table2` SET views = views+1 WHERE table.userID = NEW.userID;
    END IF;
END IF;
END//
DELIMITER ;

Which works fine with a INSERT statement.

However, I’m using REPLACE which seems to only call my DELETE trigger

CREATE TRIGGER `delete_trigger` BEFORE DELETE ON `table`
FOR EACH ROW
BEGIN
    IF (SELECT views FROM `table2` WHERE userID = OLD.userID) > 1 THEN
        UPDATE `table2` SET views = views-1 WHEREuserID = OLD.userID;
    END IF;
END//
DELIMITER ;

When using REPLACE both DELETE and INSERT triggers should be called.

I’m aware that mySQL doesn’t support multiple triggers.

What is a possible solution to get the same results (adding/subtracting views) when another table has INSERT, DELETE and REPLACE events occurring.

Answer 1

The Problem lie in my own Trigger.

REPLACE calls both Delete and Insert but this IF statement

IF (SELECT COUNT(*) FROM `table` WHERE userID = NEW.userID AND IP = new.IP) = 0 THEN

Was blocking the insert.