首先我有 2 个名为“item”和“buy_item”的表 //“stock”列在 item 表中,“qty”列是 ini buy_item 表然后我有 SQL SERVER 查询来创建这样的触发器
CREATE TRIGGER trigger1
ON dbo.buy_item
FOR UPDATE
AS begin
UPDATE item SET stock = stock - qty FROM deleted WHERE item.id = deleted.id
UPDATE item SET stock = stock + qty FROM inserted WHERE item.id = deleted.id
end
我需要帮助才能在 MYSQL 查询中创建与此查询相同的功能,我已经这样做了
CREATE TRIGGER trigger1
BEFORE UPDATE ON buy_item
FOR EACH ROW
BEGIN
UPDATE item SET stock = stock - buy_item.qty WHERE item.id=buy_item.id
UPDATE item SET stock = stock + NEW.qty WHERE item.id=buy_item.id
END
但这根本不起作用,它说语法错误
也许任何人都可以为此提供帮助
之前谢谢