Question

我有一个mysql表，每当有添加，修改/更新或删除时，我想取行并将其添加到“存档”表（在更新或删除之前）。这是一个历史档案（即发生了什么）。有没有办法在“自动”数据库层中执行此操作？有更好的方法......

Answer 1

您需要一组涵盖所有操作的触发器（插入，更新，删除）。

假设你有一张桌子

CREATE TABLE table1
(
  table1_id int not null auto_increment primary key, 
  column1 varchar(32)
);

并为您创建了以下历史记录表

CREATE TABLE table1_history
(
  history_id int not null auto_increment primary key, 
  dt datetime not null, 
  operation varchar(6) not null, 
  table1_id int not null, 
  column1 varchar(32) not null
);

现在你的触发器看起来像

CREATE TRIGGER tg_ai_table1
AFTER INSERT ON table1
FOR EACH ROW
  INSERT INTO table1_history (dt, operation, table1_id, column1)
  VALUES(NOW(), 'insert', NEW.table1_id, NEW.column1);

CREATE TRIGGER tg_au_table1
AFTER UPDATE ON table1
FOR EACH ROW
  INSERT INTO table1_history (dt, operation, table1_id, column1)
  VALUES(NOW(), 'update', NEW.table1_id, NEW.column1);

CREATE TRIGGER tg_bd_table1
BEFORE DELETE ON table1
FOR EACH ROW
  INSERT INTO table1_history (dt, operation, table1_id, column1)
  VALUES(NOW(), 'delete', OLD.table1_id, OLD.column1);

如果我们针对table1

发出以下DML声明

INSERT INTO table1 (column1) VALUES ('value1'), ('value2');
UPDATE table1 SET column1 = 'value11' WHERE table1_id = 1;
DELETE FROM table1 WHERE table1_id = 2;

table1将包含

| TABLE1_ID | COLUMN1 |
|-----------|---------|
|         1 | value11 |

table1_history将包含

| HISTORY_ID |                             DT | OPERATION | TABLE1_ID | COLUMN1 |
|------------|--------------------------------|-----------|-----------|---------|
|          1 | January, 04 2014 06:31:15+0000 |    insert |         1 |  value1 |
|          2 | January, 04 2014 06:31:15+0000 |    insert |         2 |  value2 |
|          3 | January, 04 2014 06:31:15+0000 |    update |         1 | value11 |
|          4 | January, 04 2014 06:31:15+0000 |    delete |         2 |  value2 |

这是 SQLFiddle 演示

Answer 2

尝试使用触发器

eg:

DROP TRIGGER auditlog

CREATE TRIGGER auditlog BEFORE UPDATE ON frequencies

FOR EACH ROW BEGIN  

INSERT INTO frequencies_audit select * from frequencies where freqId = NEW.freqId;

END;

复制到mysql update上的另一个表

2 个答案: