比如现在有一张表，我们要将该表复制一份，以备以后使用，那么如何使用mysql语句来实现呢？其实我们可以直接使用create ... select ... from语句来实现，具体实现方法请看下面实例。
我们先来创建一张Topic表，创建Topic表的SQL语句如下：
mysql> CREATE TABLE Topic(
-> TopicID SMALLINT NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> Name VARCHAR(50) NOT NULL,
-> InStock SMALLINT UNSIGNED NOT NULL,
-> OnOrder SMALLINT UNSIGNED NOT NULL,
-> Reserved SMALLINT UNSIGNED NOT NULL,
-> Department ENUM('Classical', 'Popular') NOT NULL,
-> Category VARCHAR(20) NOT NULL,
-> RowUpdate TIMESTAMP NOT NULL
-> );
向Topic表中插入数据：
mysql> INSERT INTO Topic (Name, InStock, OnOrder, Reserved, Department, Category) VALUES
-> ('Java', 10, 5, 3, 'Popular', 'Rock'),
-> ('JavaScript', 10, 5, 3, 'Classical', 'Opera'),
-> ('C Sharp', 17, 4, 1, 'Popular', 'Jazz'),
-> ('C', 9, 4, 2, 'Classical', 'Dance'),
-> ('C++', 24, 2, 5, 'Classical', 'General'),
-> ('Perl', 16, 6, 8, 'Classical', 'Vocal'),
-> ('Python', 2, 25, 6, 'Popular', 'Blues'),
-> ('Php', 32, 3, 10, 'Popular', 'Jazz'),
-> ('', 12, 15, 13, 'Popular', 'Country'),
-> ('', 5, 20, 10, 'Popular', 'New Age'),
-> ('', 24, 11, 14, 'Popular', 'New Age'),
-> ('UML', 42, 17, 17, 'Classical', 'General'),
-> ('',25, 44, 28, 'Classical', 'Dance'),
-> ('Oracle', 32, 15, 12, 'Classical', 'General'),
-> ('Pl/SQL', 20, 10, 5, 'Classical', 'Opera'),
-> ('Sql Server', 23, 12, 8, 'Classical', 'General');
Query OK, 16 rows affected (0.00 sec)
Records: 16 Duplicates: 0 Warnings: 0
现在我们要将这张表复制一份，具体操作如下：
mysql> CREATE TABLE Topic2
-> (
-> TopicID SMALLINT NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> Name VARCHAR(50) NOT NULL,
-> InStock SMALLINT UNSIGNED NOT NULL,
-> OnOrder SMALLINT UNSIGNED NOT NULL,
-> Reserved SMALLINT UNSIGNED NOT NULL,
-> Department ENUM('Classical', 'Popular') NOT NULL,
-> Category VARCHAR(20) NOT NULL,
-> RowUpdate TIMESTAMP NOT NULL
-> )
-> SELECT *
-> FROM Topic
这样表Topic2和Topic表不仅拥有相同的表结构，表数据也是一样的了。
例外，如果我们只需要复制表结构，不需要复制数据，也可以使用create like来实现：
create table a like users;
