[MySQL & Python] 07. 必備的SQL命令
阿新 • • 發佈：2022-04-06
資料準備
本節用到兩張資料表，他們使用depart_id進行關聯。
depart表
+----+--------+
| id | title |
+----+--------+
| 1 | 開發 |
| 2 | 運維 |
| 3 | 銷售 |
+----+--------+
info表
+----+---------+----------------+-----+-----------+
| id | name | email | age | depart_id |
+----+---------+----------------+-----+-----------+
| 1 | Leo | leo@qq.com | 41 | 1 |
| 2 | Kevin | kevin@qq.com | 45 | 2 |
| 3 | Winston | winston@qq.com | 27 | 2 |
| 4 | Kaiser | kaiser@qq.com | 40 | 3 |
| 5 | Scott | scott@qq.com | 40 | 3 |
+----+---------+----------------+-----+-----------+
複製一下語句到MySQL客戶端進行資料準備
--建立depart表，並新增內容
create table depart (
id int not null primary key auto_increment,
title varchar(20)) default charset=utf8 ;
insert into depart (title) values ('開發'),('運維'),('銷售');
--建立info表，並新增內容
create table info (
id int not null primary key auto_increment,
name varchar(20) not null,
email varchar(40) not null,
age int not null,
depart_id int) default charset=utf8;
insert into info (name, email,age,depart_id) values ('Leo','[email protected]',41,1);
insert into info (name, email,age,depart_id) values ('Kevin','[email protected]',45,2);
insert into info (name, email,age,depart_id) values ('Winston','[email protected]',27,2);
insert into info (name, email,age,depart_id) values ('Kaiser','[email protected]',40,3);
insert into info (name, email,age,depart_id) values ('Scott','[email protected]',40,3);
條件查詢 where
-
select * from 資料表 where 條件
select * from info where age = 41;
+----+------+------------+-----+-----------+
| id | name | email | age | depart_id |
+----+------+------------+-----+-----------+
| 1 | Leo | leo@qq.com | 41 | 1 |
+----+------+------------+-----+-----------+
select * from info where name != 'Leo' or 'Kaiser' or 'Kevin';
+----+---------+----------------+-----+-----------+
| id | name | email | age | depart_id |
+----+---------+----------------+-----+-----------+
| 2 | Kevin | kevin@qq.com | 45 | 2 |
| 3 | Winston | winston@qq.com | 27 | 2 |
| 4 | Kaiser | kaiser@qq.com | 40 | 3 |
| 5 | Scott | scott@qq.com | 40 | 3 |
+----+---------+----------------+-----+-----------+
select * from info where age between 41 and 45;
+----+-------+--------------+-----+-----------+
| id | name | email | age | depart_id |
+----+-------+--------------+-----+-----------+
| 1 | Leo | leo@qq.com | 41 | 1 |
| 2 | Kevin | kevin@qq.com | 45 | 2 |
+----+-------+--------------+-----+-----------+
mysql> select * from info where id in (1,4);
+----+--------+---------------+-----+-----------+
| id | name | email | age | depart_id |
+----+--------+---------------+-----+-----------+
| 1 | Leo | leo@qq.com | 41 | 1 |
| 4 | Kaiser | kaiser@qq.com | 40 | 3 |
+----+--------+---------------+-----+-----------+
select * from info where id not in (1,4,5);
+----+---------+----------------+-----+-----------+
| id | name | email | age | depart_id |
+----+---------+----------------+-----+-----------+
| 2 | Kevin | kevin@qq.com | 45 | 2 |
| 3 | Winston