MySQL add columns, modify columns, delete columns

Source: Internet
Author: User
Tags mysql view

ALTER table: Add, modify, delete table columns, constraints, and other table definitions.

    • View column: Desc table name;
    • Modify table name: ALTER TABLE T_book Rename to BBB;
    • Add column: ALTER TABLE name add column name varchar (30);
    • Delete column: ALTER TABLE table name drop column name;
    • Modify Column name Mysql:alter table BBB change nnnnn hh int;
    • Modify the column name Sqlserver:exec sp_rename ' t_student.name ', ' nn ', ' column ';
    • Modify the Column name Oracle:lter table BBB Rename column nnnnn to HH int;
    • Modify Column properties: ALTER TABLE T_book modify name varchar (22);

Sp_rename:sqlserver built-in stored procedures, with the definition of modified tables.



MySQL view constraints, add constraints, remove constraints add columns, modify columns, delete columns

    • View field information for table: DESC table name;
    • View all information about the table: Show create table table name;
    • add PRIMARY KEY constraint: ALTER TABLE name add constraint primary key (shape: PK _ Table Name) primary key table name (primary key field);
    • add FOREIGN KEY constraint: ALTER TABLE from TABLE ADD constraint foreign key (shape: FK _ From Table _ Main Table) foreign key from table (foreign key field) references Main Table (primary key field);
    • Modify table name: ALTER TABLE T_book Rename to BBB;
    • add column: ALTER TABLE name add column name varchar (+);
    • Modify column name Mysql:alter table BBB change nnnnn hh int;
    • Modify column name Sqlserver:exec sp_rename ' T_ Student.name ', ' nn ', ' column ';
    • Modify column name Oracle:alter table BBB Rename column nnnnn to HH int;
    • );

Sp_rename:sqlserver built-in stored procedures, with the definition of modified tables.

http://blog.csdn.net/ws84643557/article/details/6939846

MySQL add columns, modify columns, delete columns

Related Article

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.