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MySQL – Clone Tables

There may be a situation when you need an exact copy of a table and CREATE TABLE … SELECT doesn’t suit your purposes because the copy must include the same indexes, default values and so forth.

You can handle this situation by following the steps given below −

  • Use SHOW CREATE TABLE to get a CREATE TABLE statement that specifies the source table’s structure, indexes and all.
  • Modify the statement to change the table name to that of the clone table and execute the statement. This way, you will have the exact clone table.
  • Optionally, if you need the table contents copied as well, issue an INSERT INTO … SELECT statement, too.

Example

Try out the following example to create a clone table for tutorials_tbl.

Step 1 − Get the complete structure about the table.

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 = MyISAM
1 row in set (0.00 sec)

ERROR:
No query specified

Step 2 − Rename this table and create another table.

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 = MyISAM;
Query OK, 0 rows affected (1.80 sec)

Step 3 − After executing step 2, you will create a clone table in your database. If you want to copy data from old table then you can do it by using INSERT INTO… SELECT statement.

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

Finally, you will have an exact clone table as you wanted to have.

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