是否可以将NEW和OLD表从触发器传递到MySQL中的过程中? [英] Is it possible to pass the NEW and the OLD tables from a trigger into a procedure in MySQL?

问题描述

是否可以将NEW和OLD表从触发器传递到MySQL中的过程中? 我怀疑没有，因为没有过程可以接受的表这样的数据类型. 有任何可行的解决方法?

Is it possible to pass the NEW and the OLD tables from a trigger into a procedure in MySQL? I suspect no, since there is no such a datatype as table that a procedure accepts. Any workarounds possible?

理想情况下，它看起来像这样:

Ideally it would look like this:

CREATE TRIGGER Product_log AFTER UPDATE ON Product
  FOR EACH ROW BEGIN
    call logChanges(OLD, NEW);
  END;

推荐答案

这是不可能的，因为没有新的或旧的表.整个触发器与 the 表相关-新"和旧"指的是行及其在之前和之后包含的值触发的事件.换句话说，您的示例将是:

it's not possible because there is no NEW or OLD table. The entire trigger is related to the table - the "new" and "old" refer to the rows and the values they contained before and after the event that was triggered. In other words, your example would be:

call logChanges(OLD.customername, NEW.customername)

您还可以将所有OLD数据保存在历史表中(我希望logchange仍然可以这样做)，基本上是生产表的克隆，如下所示:

You could also save all the OLD data in a history table (which I expect logchanges does anyways), basically being a clone of the production table something like this:

BEGIN
    IF OLD.customer_name != NEW.customer_name
    THEN
            INSERT INTO myTable_chagne_history
                (
                    customer_id    ,
                    customer_name  ,
                    another_field  ,
                    edit_time
                )
                VALUES
                (
                    OLD.customer_id,
                    OLD.customer_name,
                    OLD.another_field  ,
                    NEW.time_edit_was_made
                );
    END IF;
END;

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