MySQL replicates table structure, table data, and modify primary key

MySQL View table structure command

Show columns from table name;

1, copy table structure and data to new Table CREATE table new Table select * from the old table This method will copy all the contents of oldtable, of course, we can use delete from newtable; But one of the worst things about this approach is that the new table has no properties such as primary key, Extra (auto_increment), and so on.     You need to use "alter" to add, and it's easy to mistake. 2. Copy table structure to new Table CREATE table new Table select * from old table where 1=2 or CREATE table new table like old table, this also need to change primary key change primary key: ALTER TABLE TB add primary ke Y (Id,di2);

ID,ID2 indicates that both columns are treated as primary keys, as well as one as the primary key.

Add field 3 alter table tbname add  field 3 varchar (10); Delete primary key   alter table  tbname drop primary key; Add primary key  alter table tbname add primary key (field-by-column);