在MySQL中操作克隆表的教程_MySQL
可能有一种情况,当需要一个完全相同的副本表CREATE TABLE ... SELECT不适合需要,因为副本必须包含相同的索引,默认值,依此类推。
按下面的步骤,可以处理这种情况。
- 使用SHOW CREATE TABLE得到一个CREATE TABLE语句中指定源表的结构,索引等。
- 修改语句更改表名称的克隆表,并执行该语句。通过这种方式将有确切的克隆表。
- 或者,如果需要进行表的内容复制,使用INSERT INTO ... SELECT语句也可以搞定。
实例:
试试下面的例子来创建一个克隆表tutorials_tbl
步骤 1:
有关表获取完整的结构
mysql> SHOW CREATE TABLE tutorials_tbl \G; *************************** 1. row *************************** Table: tutorials_tbl Create Table: CREATE TABLE `tutorials_tbl` ( `tutorial_id` int(11) NOT NULL auto_increment, `tutorial_title` varchar(100) NOT NULL default '', `tutorial_author` varchar(40) NOT NULL default '', `submission_date` date default NULL, PRIMARY KEY (`tutorial_id`), UNIQUE KEY `AUTHOR_INDEX` (`tutorial_author`) ) TYPE=InnoDB 1 row in set (0.00 sec) ERROR: No query specified
步骤 2:
重命名此表,并创建另一个表
mysql> CREATE TABLE `clone_tbl` ( -> `tutorial_id` int(11) NOT NULL auto_increment, -> `tutorial_title` varchar(100) NOT NULL default '', -> `tutorial_author` varchar(40) NOT NULL default '', -> `submission_date` date default NULL, -> PRIMARY KEY (`tutorial_id`), -> UNIQUE KEY `AUTHOR_INDEX` (`tutorial_author`) -> ) TYPE=InnoDB; Query OK, 0 rows affected (1.80 sec)
步骤 3:
在执行步骤2的克隆数据库的表中。如果想从旧表中的数据复制,那么可以通过使用INSERT INTO... SELECT语句。
mysql> INSERT INTO clone_tbl (tutorial_id, -> tutorial_title, -> tutorial_author, -> submission_date) -> SELECT tutorial_id,tutorial_title, -> tutorial_author,submission_date, -> FROM tutorials_tbl; Query OK, 3 rows affected (0.07 sec) Records: 3 Duplicates: 0 Warnings: 0
最后,将有确切的克隆表。

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