如何在MySQL中执行多个选择查询？
要在MySQL中执行多个选择查询，请使用DELIMITER的概念。让我们首先创建一个表-
mysql> create table DemoTable1 ( Title text )ENGINE=MyISAM;
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable1 values('The database MySQL is less popular than MongoDB') ;
mysql> insert into DemoTable1 values('Java language uses MySQL database');
mysql> insert into DemoTable1 values('Node.js uses the MongoDB') ;使用select语句显示表中的所有记录-
mysql> select *from DemoTable1;
这将产生以下输出-
+-------------------------------------------------+ | Title | +-------------------------------------------------+ | The database MySQL is less popular than MongoDB | | Java language uses MySQL database | | Node.js uses the MongoDB | +-------------------------------------------------+ 3 rows in set (0.00 sec)
以下是创建第二个表的查询-
mysql> create table DemoTable2 ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY );
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable2 values(),(),(),(),(),(),(),(),(); Records: 9 Duplicates: 0 Warnings: 0
使用select语句显示表中的所有记录-
mysql> select *from DemoTable2;
这将产生以下输出-
+----+ | Id | +----+ | 1 | | 2 | | 3 | | 4 | | 5 | | 6 | | 7 | | 8 | | 9 | +----+ 9 rows in set (0.00 sec)
以下是执行多个选择查询的查询-
mysql> DELIMITER // mysql> select *from DemoTable1; select *from DemoTable2; //
这将产生以下输出，显示两个select语句的结果-
+-------------------------------------------------+ | Title | +-------------------------------------------------+ | The database MySQL is less popular than MongoDB | | Java language uses MySQL database | | Node.js uses the MongoDB | +-------------------------------------------------+ 3 rows in set (0.00 sec) +----+ | Id | +----+ | 1 | | 2 | | 3 | | 4 | | 5 | | 6 | | 7 | | 8 | | 9 | +----+ 9 rows in set (0.03 sec)