[MySQL & Python] 05. MySQL的数据进行增删改查
添加数据
insert into 表名 (列名, 列名) values (值1, 值2)
--插入一条记录
mysql> INSERT INTO test_insert(name, email)
values ('Leo', 'leo@qq.com');
--一次插入两条记录
mysql> INSERT INTO test_insert(name, email)
values ('Kevin', 'kw@qq.com'),('Winston', 'WW@qq.com');
删除数据
delete from 表名;
delete from 表名 where 条件;
mysql> DELETE FROM test_insert
WHERE name like 'Win%' and age > 4 ;
修改数据
update 表名 set 列名 = 值 ;
update 表名 set 列名 = 值 where 条件 ;
mysql> update data set age = 45 ; --age列的所有数据改为45
mysql> update data set age = 41 --age列特定数据改为41
-> where name = 'Leo';
--在原先数据基础上进行操作。
mysql> update data set age = age+1 ;
mysql> update data set name = concat('slq-' , name);
mysql> select * from data;
+----+-------------+------+----------------+
| id | name | age | email |
+----+-------------+------+----------------+
| 1 | slq-Leo | 42 | leo@qq.com |
| 2 | slq-Kevin | 46 | kevin@qq.com |
| 3 | slq-winston | 46 | winston@qq.com |
+----+-------------+------+----------------+
select * from 表名;
select 列名,列名 from 表名;
select 列名 as 别名 from 表名;
select * from 表名 where 条件;
select id as 标识, name as 姓名, age as 年龄 from data;
+--------+-------------+--------+
| 标识 | 姓名 | 年龄 |
+--------+-------------+--------+
| 1 | slq-Leo | 42 |
| 2 | slq-Kevin | 46 |
| 3 | slq-winston | 46 |
+--------+-------------+--------+
--即使列名不存在,也可以select
mysql> select 'SLQ' as 酒店代码, id as 标识, name as 姓名, age as 年龄 from data;
+--------------+--------+-------------+--------+
| 酒店代码 | 标识 | 姓名 | 年龄 |
+--------------+--------+-------------+--------+
| SLQ | 1 | slq-Leo | 42 |
| SLQ | 2 | slq-Kevin | 46 |
| SLQ | 3 | slq-winston | 46 |
+--------------+--------+-------------+--------+
posted on 2022-04-06 10:08 LeoZhangJing 阅读(27) 评论(0) 编辑 收藏 举报