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 steps.
- 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 exact clone table.
- Optionally, If you need the table contents copied as well, issue an INSERT INTO ... SELECT statement, too.
Example:
Try out following example to create a clone table for tutorials_tbl
Step 1:
Get complete structure about 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 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 exact clone table as you wanted to have.
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