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

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