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.
Reprint http://blog.csdn.net/ws84643557/article/details/6939846
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);
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- Modify table name: ALTER TABLE T_book Rename to BBB;
- add column: ALTER TABLE name add column name varchar (+);
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- 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 modifications to the table definition.
