SQL再学习plus
作者:互联网
DML
添加数据
代码实现
mysql> select * from stu;
+------+------+------+
| name | id | sex |
+------+------+------+
| xue | 1 | 1 |
| he | 2 | 2 |
+------+------+------+
2 rows in set (0.01 sec)
mysql> insert into stu(name,id,sex) values("小爽",1,"女");
Query OK, 1 row affected (0.01 sec)
mysql> select * from stu;
+------+------+------+
| name | id | sex |
+------+------+------+
| xue | 1 | 1 |
| he | 2 | 2 |
| 小爽 | 1 | 女 |
+------+------+------+
3 rows in set (0.01 sec)
修改数据
代码实现
mysql> select * from stu;
+------+------+------+
| name | id | sex |
+------+------+------+
| xue | 1 | 男 |
| he | 2 | 2 |
| 小爽 | 1 | 女 |
| 小程 | 2 | 男 |
+------+------+------+
4 rows in set (0.02 sec)
mysql> update stu set sex = "男" where name = "he";
Query OK, 1 row affected (0.03 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from stu;
+------+------+------+
| name | id | sex |
+------+------+------+
| xue | 1 | 男 |
| he | 2 | 男 |
| 小爽 | 1 | 女 |
| 小程 | 2 | 男 |
+------+------+------+
4 rows in set (0.00 sec)
删除数据
代码实现
mysql> select * from stu;
+------+------+------+
| name | id | sex |
+------+------+------+
| xue | 1 | 男 |
| he | 2 | 男 |
| 小爽 | 1 | 女 |
| 小程 | 2 | 男 |
+------+------+------+
4 rows in set (0.00 sec)
mysql> delete from stu where name = "he";
Query OK, 1 row affected (0.01 sec)
mysql> select * from stu;
+------+------+------+
| name | id | sex |
+------+------+------+
| xue | 1 | 男 |
| 小爽 | 1 | 女 |
| 小程 | 2 | 男 |
+------+------+------+
3 rows in set (0.00 sec)
DQL
代码实现
mysql> select name , sex from stu;
+------+------+
| name | sex |
+------+------+
| xue | 男 |
| 小爽 | 女 |
| 小程 | 男 |
+------+------+
3 rows in set (0.00 sec)
代码实现
mysql> select distinct sex from stu;
+------+
| sex |
+------+
| 男 |
| 女 |
+------+
2 rows in set (0.03 sec)
起别名
代码实现
mysql> select name as "姓名",sex "性别" from stu;
+------+------+
| 姓名 | 性别 |
+------+------+
| xue | 男 |
| 小爽 | 女 |
| 小程 | 男 |
+------+------+
3 rows in set (0.00 sec)
标签:+------+------+------+,name,mysql,sex,学习,stu,sec,SQL,plus 来源: https://www.cnblogs.com/he-cheng/p/16023010.html