Related commands for MySQL fields

First, add fields

1. Add fields

ALTER TABLE name add new field Name Type field, ALTER TABLE student add Heig;

2. Increase the primary key

ALTER TABLE name add new field type default 0 NOT null Auto_increment,add primary key; (new field) ALTER TABLE student Add name type default 0 NOT null Auto_increment,add primary key;

Second, delete the field

1. Delete a field

ALTER TABLE table name drop column field name

ALTER TABLE student drop column Heig;

Third, change the field

1. Modify the field name

ALTER TABLE name change old field name new field name type; ALTER TABLE atudent change name class varchar (6);

2. Modify the field type

ALTER TABLE name change field name new type;

ALTER TABLE student change name char (6)

Iv. query fields

Related commands for MySQL fields