MySQL中复制数据表中的数据到新表中的操作教程_MySQL
MySQL是不支持SELECT … INTO语法的,使用INSERT INTO … SELECT替代相同用法,下面我们我们这里简答分一下新表存在和不存在两种情况,具体使用不同的语句。
1.新表不存在
复制表结构即数据到新表
create table new_table select * from old_talbe;
这种方法会将old_table中所有的内容都拷贝过来,用这种方法需要注意,new_table中没有了old_table中的primary key,Extra,auto_increment等属性,需要自己手动加,具体参看后面的修改表即字段属性.
只复制表结构到新表
# 第一种方法,和上面类似,只是数据记录为空,即给一个false条件 create table new_table select * from old_table where 1=2; # 第二种方法 create table new_table like old_table;
2.新表存在
复制旧表数据到新表(假设两个表结构一样)
insert into new_table select * from old_table;
复制旧表数据到新表(假设两个表结构不一样)
insert into new_table(field1,field2,.....) select field1,field2,field3 from old_table;
复制全部数据
select * into new_table from old_table;
只复制表结构到新表
select * into new_talble from old_table where 1=2;
3.实例
(1)表不存在复制
mysql>show tables; +-----------------+ |Tables_in_test1 | +-----------------+ |cpu_stat | |test1 | |test2 | |test3 | +-----------------+ 4rows in set (0.02 sec) mysql> create tabletest4 as select * from test1 where 1=0; //仅复制表结构 QueryOK, 0 rows affected (0.06 sec) Records:0 Duplicates: 0 Warnings: 0 mysql> create tabletest5 as select * from test1; //把表test1所有内容复制为test5 QueryOK, 7 rows affected (0.11 sec) Records:7 Duplicates: 0 Warnings: 0
(2)表已经存在复制
mysql> create table test6(id int not null auto_increment primary key, name varchar(20)); Query OK, 0 rows affected (0.13 sec) mysql> insert into test6(name) select name from test1; //只复制name列 Query OK, 7 rows affected (0.06 sec) Records: 7 Duplicates: 0 Warnings: 0 mysql> select * from test6; +----+-------+ | id | name | +----+-------+ | 1 | wu | | 2 | terry | | 3 | tang | …… 7 rows in set (0.00 sec)

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