Mysql copies the table structure, table data, and modifies the primary key.

Mysql command to view the table structure showcolumnsfrom table name; 1. Copy the table structure and data to the new table CREATETABLE new table SELECT * FROM old table this method will copy all content in oldtable, of course, we can use deletefromnewtable; to delete it. However, the worst thing about this method is that the new table does not have

Mysql command to view the TABLE structure show columns from TABLE name; 1. Copy the TABLE structure and data to the new table create table new table select * FROM old TABLE this method will copy all content in oldtable, of course, we can delete it using delete from newtable. However, the worst thing about this method is that the new table does not have

Mysql Command for viewing table Structures

Show columns from table name;

1. Copy the table structure and data to the new table
Create table new table select * FROM old TABLE
This method will copy all content in oldtable. Of course, we can use delete from newtable; to delete it.
However, the worst thing about this method is that the new table does not have the primary key, Extra (auto_increment) and other attributes of the old table. You need to use "alter" to add it yourself, and it is easy to make a mistake.


2. Only copy the table structure to the new table
Create table new table select * FROM old table where 1 = 2
Or create table new table like old TABLE, which also needs to change the primary key

Change primary key: Alter table tb add primary key (id, di2 );

Id. id2 indicates that the two columns are treated as the primary key at the same time, or you can use one of them as the primary key.

Add Field 3 alter table tbname add field 3 varchar (10 );
Delete the primary key alter table tbname drop primary key;
Add the primary key alter table tbname add primary key (Field 1, 2, 3 );