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MySQL常用DDL,DML语句及外键创建

WBOY
WBOYOriginal
2016-06-07 17:00:261155browse

Query OK, 0 rows affected (0.05 sec)修改表列类型:ALTER TABLE orderitems MODIFY date DATE;4.插入等(DML): insert into u

1.创建库:
CREATE DATABASE OrderTicket;
Query OK, 1 row affected (0.00 sec)
2.使用库:
mysql> use OrderTicket;
Database changed
mysql> show tables;
Empty set (0.00 sec)

mysql> use OrderTicket;
Database changed
3.创建表等(DDL):
mysql> CREATE TABLE orderitems(ID int(8)not null auto_increment,FLIGHT_ID BIGINT
(12),DATE DATETIME,PRIMARY KEY(ID))

Query OK, 0 rows affected (0.05 sec)
修改表列类型:
ALTER TABLE orderitems MODIFY  date DATE;
4.插入等(DML):
insert into users values(004,'004','家源','root','M','15078827641','blues-cen@hotmail.com');
查询,修改,删除等。

5.创建外键:

fights为被参照表,原先没有设置其ENGINE类型,orderitems为参照表。

被参照表中:
1.使用ALTER TABLE fights ENGINE=INNODB.

参照表中:
1.mysql> CREATE TABLE orderitems(ID BIGINT(20) NOT NULL AUTO_INCREMENT,fight_id BIGINT(20) NOT NULL,date DATETIME,INDEX(fight_id),PRIMARY KEY(ID), FOREIGN KEY(fight_id) REFERENCES fights(ID) ON DELETE CASCADE ON UPDATE CASCADE )engine=innodb;

Query OK, 0 rows affected (0.06 sec)
注意细节问题:
(1)TABLE 的名称不要写成TABEL.
(2)mysql(dos)程序下使用复制粘贴:
选定->标题栏右键编辑->复制,将命令行选定的内容复制到剪切板。
粘贴:复制要粘贴的文本内容到剪切板->标题编辑->粘贴到当前光标输入点。
(3)mysql(dos)插入的位置是在:当前光标的前一个位置插入。
(4)插入可以用VALUES (1,,'***','***'),(2,'**','***');实现多行一次插入。

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