MySQL_Table_Create_Describe_Alter_Drop

摘要: Create -- Describe -- Alter -- Drop

1. Create table

i. Normal

CREATE TABLE t_bookType(
id int primary key auto_increment,
bookTypeName varchar(20),
bookTyptDesc varchar(200)
);

ii. With index

create table t_book(
id int primary key auto_increment,
bookName varchar(20),
author varchar(10),
price decimal(6,2),
bookTypeId int,
constraint `forKey` foreign key (`bookTypeId`) references `t_bookType`(`id`)
);

2. Describe table

desc t_bookType;
show create table t_bookType;

3. Alter

i. Table rename

alter table t_book rename t_book2;

ii. Rename field

alter table t_book change bookName bookName2 varchar(20);

iv. Add field

alter table t_book add testField int after author;
alter table t_book add testField int first;
alter table tableName add fieldNameNew dataType ［constraint condition］ first|(after fieldNameOld)

v. Drop field

alter table t_book drop testField;

4. Drop

i. Drop table

drop table t_book;

Be careful:

The PARENT table could not be deleted, it has to delete the sub table first!