1

有人帮我写了以下内容：

CREATE TRIGGER update_stats AFTER UPDATE ON user_hours FOR EACH ROW
INSERT INTO hours_statistics (user_id, opportunity_id, completed_hours) VALUES
(OLD.user_id, OLD.opportunity_id, -OLD.completed_hours),
(NEW.user_id, NEW.opportunity_id, +NEW.completed_hours)
ON DUPLICATE KEY UPDATE
completed_hours = completed_hours + VALUES(completed_hours);

但是，触发器应仅针对以下情况运行：

UPDATE user_hours JOIN user_calendar USING (user_calendar_id, opportunity_id)
SET    user_hours.completed_hours = agreed_hours,
user_hours.hours_committed = 'completed'
WHERE  user_hours.hours_committed = 'accepted' 
AND user_hours.completed_hours IS NULL
AND user_calendar.date_start = CURRENT_DATE();

就目前而言，如果手动调整管理员或用户的 completed_hours，更新触发器仍会运行。我想在代码中添加一些 IF 语句，但我的尝试都未能创建触发器。

我正在寻找类似的东西：

CREATE TRIGGER update_stats AFTER UPDATE ON user_hours FOR EACH ROW
IF hours_committed = 'completed' THEN
INSERT INTO hours_statistics (user_id, opportunity_id, completed_hours) VALUES
(OLD.user_id, OLD.opportunity_id, -OLD.completed_hours),
(NEW.user_id, NEW.opportunity_id, +NEW.completed_hours)
ON DUPLICATE KEY UPDATE
completed_hours = completed_hours + VALUES(completed_hours);
END IF
END

任何人都可以提供帮助，除非满足特定条件，否则不希望触发器运行，这让我们需要的代码工作很烦人，但这会在运行调整查询之外的几天内造成问题。

提前致谢。

标记

4

1 回答 1

2

触发器将始终运行，您需要将该条件添加到触发器的主体中，并比较新更新的列 ( new.column)：

DELIMITER //

CREATE TRIGGER update_stats AFTER UPDATE ON user_hours 
FOR EACH ROW
BEGIN
  IF NEW.hours_committed = 'completed' THEN
    INSERT INTO hours_statistics (user_id, opportunity_id, completed_hours) VALUES
      (OLD.user_id, OLD.opportunity_id, -OLD.completed_hours),
      (NEW.user_id, NEW.opportunity_id, +NEW.completed_hours)
    ON DUPLICATE KEY UPDATE
      completed_hours = completed_hours + VALUES(completed_hours);
  END IF;
END//
于 2012-08-26T15:35:53.417 回答