使用 JOIN 来选择具有多个条件(使用 AND)的记录?
mysqlmysqli database
让我们首先创建一个演示表 −
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。 查询语句如下 −
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;
这是输出 −
+----------+------------+----------------------+ | 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)
以下查询用于选择同时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';
以下是输出 −
+------------+ | PersonName | +------------+ | Carol | | Sam | +------------+ 2 rows in set (0.00 sec)
