可否使用 AND 来结合多个条件来选择记录?


让我们首先创建一个 demo 表 −

mysql> create table selectPerson
   -> (
   -> PersonId int NOT NULL AUTO_INCREMENT PRIMARY KEY,
   -> PersonName varchar(20),
   -> PersonFavouriteFruit varchar(60)
   -> );
Query OK, 0 rows affected (0.58 sec)

使用 insert 命令在表中插入一些记录。查询如下 −

mysql> insert into selectPerson(PersonName,PersonFavouriteFruit) values('John','Banana');
Query OK, 1 row affected (0.14 sec)
mysql> insert into selectPerson(PersonName,PersonFavouriteFruit) values('John','Blackberry');
Query OK, 1 row affected (0.12 sec)
mysql> insert into selectPerson(PersonName,PersonFavouriteFruit) values('John','Blueberry');
Query OK, 1 row affected (0.12 sec)
mysql> insert into selectPerson(PersonName,PersonFavouriteFruit) values('Carol','Apple');
Query OK, 1 row affected (0.19 sec)
mysql> insert into selectPerson(PersonName,PersonFavouriteFruit) values('Carol','Avocado');
Query OK, 1 row affected (0.17 sec)
mysql> insert into selectPerson(PersonName,PersonFavouriteFruit) values('Carol','Banana');
Query OK, 1 row affected (0.20 sec)
mysql> insert into selectPerson(PersonName,PersonFavouriteFruit) values('Sam','Ackee');
Query OK, 1 row affected (0.15 sec)
mysql> insert into selectPerson(PersonName,PersonFavouriteFruit) values('Sam','Apple');
Query OK, 1 row affected (0.89 sec)
mysql> insert into selectPerson(PersonName,PersonFavouriteFruit) values('Sam','Apricots');
Query OK, 1 row affected (0.12 sec)
mysql> insert into selectPerson(PersonName,PersonFavouriteFruit) values('Sam','Banana');
Query OK, 1 row affected (0.27 sec)

使用 select 语句显示表中的所有记录。查询如下 −

mysql> select *from selectPerson;

以下是输出 −

+----------+------------+----------------------+
| PersonId | PersonName | PersonFavouriteFruit |
+----------+------------+----------------------+
| 1        | John       | Banana               |
| 2        | John       | Blackberry           |
| 3        | John       | Blueberry            |
| 4        | Carol      | Apple                |
| 5        | Carol      | Avocado              |
| 6        | Carol      | Banana               |
| 7        | Sam        | Ackee                |
| 8        | Sam        | Apple                |
| 9        | Sam        | Apricots             |
| 10       | Sam        | Banana               |
+----------+------------+----------------------+
10 rows in set (0.00 sec)

以下是查询喜欢苹果和香蕉的人 −

mysql> SELECT tbl1.PersonName
   -> FROM selectPerson tbl1 JOIN selectPerson tbl2 on tbl1.PersonName =tbl2.PersonName
   -> WHERE
   -> tbl1.PersonFavouriteFruit='Banana'
   -> and
   -> tbl2.PersonFavouriteFruit='Apple';

以下为输出 −

+------------+
| PersonName |
+------------+
| Carol      |
| Sam        |
+------------+
2 rows in set (0.00 sec)

更新时间: 30-7-2019

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