MySQL: Syntax error when creating a trrigger

Question

I am simply trying to insert a row into a parent table if the row doesn't exist in the parent table. I am getting "Statement incomplete. Expecting ';'" on the "INSERT INTO" line.

CREATE TRIGGER SellsInsertAlcoholAdd 
AFTER INSERT ON Sells
FOR EACH ROW
BEGIN
    IF(NEW.`Alcohol name` NOT IN
        (SELECT `Alcohol name` FROM Alcohol))
    THEN INSERT INTO Alcohol VALUES(NEW.`Alcohol Name`, NEW.`Type`, NEW.ABV, NEW.Manufacturer);
    END IF;
END

Answer 1

You are unnecessarily getting all the Alcohol name values, and then checking for the NEW value within it. Instead, you can change to using NOT EXISTS().

You also need to change DELIMITER to something else (other than ;) at the beginning. At the end, redefine it back to ;

DELIMITER $$
CREATE TRIGGER SellsInsertAlcoholAdd 
AFTER INSERT ON Sells
FOR EACH ROW
BEGIN
    IF NOT EXISTS(SELECT 1 FROM Alcohol 
                  WHERE `Alcohol name` = NEW.`Alcohol name`) THEN
      INSERT INTO Alcohol 
      VALUES(NEW.`Alcohol Name`, NEW.`Type`, NEW.ABV, NEW.Manufacturer);
    END IF;
END $$
DELIMITER ;