創建mysql觸發器時出現1064錯誤

Question

我正在嘗試創建mysql觸發器，但出現錯誤

錯誤＃1064-您的SQL語法有錯誤； 檢查與您的MySQL服務器版本相對應的手冊，以找到在第14行的''附近使用的正確語法

這是我的SQL腳本

delimiter $$
CREATE TRIGGER `update_account_balance_after_transfer` AFTER INSERT ON `balance_transfer`
 FOR EACH ROW  
    BEGIN
    IF(NEW.from_account_type='CUSTOMER') THEN
        UPDATE customer c SET c.balance = c.balance-NEW.amount WHERE c.customer_id= NEW.from_account_id;
    ELSE IF(NEW.from_account_type='Vendor') THEN
        UPDATE vendor V SET v.balance = v.balance-NEW.amount WHERE v.vendor= NEW.from_account_id;
    END IF;
    IF(NEW.to_account_type='VENDOR') THEN
        UPDATE customer c SET c.balance = c.balance+NEW.amount WHERE c.customer_id= NEW.to_account_id;
    ELSE IF(NEW.to_account_type='Vendor') THEN
        UPDATE vendor V SET v.balance = v.balance+NEW.amount WHERE v.vendor= NEW.to_account_id;
    END IF;
END $$
delimiter ;

Answer 1

刪除ELSE和IF之間的空間。 它應為ELSEIF ，如下所示。

delimiter $$
CREATE TRIGGER `update_account_balance_after_transfer` AFTER INSERT ON `balance_transfer`
 FOR EACH ROW  
    BEGIN
    IF(NEW.from_account_type='CUSTOMER') THEN
        UPDATE customer c SET c.balance = c.balance-NEW.amount WHERE c.customer_id= NEW.from_account_id;
    ELSEIF(NEW.from_account_type='Vendor') THEN
        UPDATE vendor V SET v.balance = v.balance-NEW.amount WHERE v.vendor= NEW.from_account_id;
    END IF;
    IF(NEW.to_account_type='VENDOR') THEN
        UPDATE customer c SET c.balance = c.balance+NEW.amount WHERE c.customer_id= NEW.to_account_id;
    ELSEIF(NEW.to_account_type='Vendor') THEN
        UPDATE vendor V SET v.balance = v.balance+NEW.amount WHERE v.vendor= NEW.to_account_id;
    END IF;
END $$
delimiter ;

MySQL IF語法

在此處查看演示