mysql basic statement(2)

table

1. Modify table name (1): alter table table name rename [to | as] New table name modify table name (2):
2. alter table table name to new table name

Field

3. New fields: alter table table name add field name field type [constraint conditions] [after | first field name]

• [after | first field name]: position

4. Delete field name: alter table table name drop [column] field name
5. Modification type (1): alter table table name modify field name field type [constraint conditions] [after | first field name]
6. Modification type (two): alter table table name change original field name field name field type [constraint condition] [after | first field name]
7. Add primary key: alter table table name add primary key (field name)
8. Delete the primary key: alter table table name drop primary key
9. Add unique constraint: alter table table name unique (field name)
10. Delete the unique constraint: alter table table name drop index index
11. Add default value: alter table table name alter field name set default''default value''
12. Delete the default value: alter table table name alter field name drop default
13. Modified self-growth: alter table table name aotu_increment = new start
14. Modify the table name (1): alter table table name rename [to | as] new table name
15. Modify table name (two): alter table table name to new table name

recording

1. New record (1): insert into table name (field name 1, field name 2) values ​​(value 1 | default, value 2)
2. New record (2): update table name field name set value