MySQL连接查询实例详解
网络 2018-06-29 1220
本文实例讲述了MySQL连接查询。分享给大家供大家参考，具体如下：
创建表suppliers：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 | CREATE TABLE suppliers ( s_id int NOT NULL AUTO_INCREMENT, s_name char(50) NOT NULL, s_city char(50) NULL, s_zip char(10) NULL, s_call CHAR(50) NOT NULL, PRIMARY KEY (s_id) ) ; INSERT INTO suppliers(s_id, s_name,s_city, s_zip, s_call) VALUES(101,'FastFruit Inc.','Tianjin','300000','48075'), (102,'LT Supplies','Chongqing','400000','44333'), (103,'ACME','Shanghai','200000','90046'), (104,'FNK Inc.','Zhongshan','528437','11111'), (105,'Good Set','Taiyuang','030000', '22222'), (106,'Just Eat Ours','Beijing','010', '45678'), (107,'DK Inc.','Zhengzhou','450000', '33332'); |
内连接
1 2 3 | SELECT suppliers.s_id, s_name,f_name, f_price FROM fruits ,suppliers WHERE fruits.s_id = suppliers.s_id; |
使用 inner join 语法进行内连接查询
1 2 3 | SELECT suppliers.s_id, s_name,f_name, f_price FROM fruits INNER JOIN suppliers ON fruits.s_id = suppliers.s_id; |
创建表orders：
1 2 3 4 5 6 7 8 9 10 11 12 13 | CREATE TABLE orders ( o_num int NOT NULL AUTO_INCREMENT, o_date datetime NOT NULL, c_id int NOT NULL, PRIMARY KEY (o_num) ) ; INSERT INTO orders(o_num, o_date, c_id) VALUES(30001, '2008-09-01', 10001), (30002, '2008-09-12', 10003), (30003, '2008-09-30', 10004), (30004, '2008-10-03', 10005), (30005, '2008-10-08', 10001); |
左连接
1 2 3 | SELECT customers.c_id, orders.o_num FROM customers LEFT OUTER JOIN orders ON customers.c_id = orders.c_id; |
右连接
1 2 3 | SELECT customers.c_id, orders.o_num from customers RIGHT OUTER JOIN orders ON customers.c_id = orders.c_id; |
复合条件连接查询
1 2 3 4 5 6 7 | SELECT customers.c_id, orders.o_num FROM customers INNER JOIN orders ON customers.c_id = orders.c_id AND customers.c_id = 10001; SELECT suppliers.s_id, s_name,f_name, f_price FROM fruits INNER JOIN suppliers ON fruits.s_id = suppliers.s_id ORDER BY fruits.s_id; |
【例.46】在fruits表和suppliers表之间使用内连接查询，查询之前，查看两个表的结构
1 2 3 | SELECT suppliers.s_id, s_name,f_name, f_price FROM fruits ,suppliers WHERE fruits.s_id = suppliers.s_id; |
【例.47】在fruits表和suppliers表之间使用INNER JOIN语法进行内连接查询
1 2 3 | SELECT suppliers.s_id, s_name,f_name, f_price FROM fruits INNER JOIN suppliers ON fruits.s_id = suppliers.s_id; |
【例.48】查询供应f_id='a1'的水果供应商提供的其他水果种类
1 2 3 | SELECT f1.f_id, f1.f_name FROM fruits AS f1, fruits AS f2 WHERE f1.s_id = f2.s_id AND f2.f_id = 'a1'; |
【例.49】在customers表和orders表中，查询所有客户，包括没有订单的客户，SQL语法如下
1 2 3 | SELECT customers.c_id, orders.o_num FROM customers LEFT OUTER JOIN orders ON customers.c_id = orders.c_id; |
【例.50】在customers表和orders表中，查询所有订单，包括没有客户的订单
1 2 3 | SELECT customers.c_id, orders.o_num from customers RIGHT OUTER JOIN orders ON customers.c_id = orders.c_id; |
【例.51】在customers表和orders表中，使用INNER JOIN语法查询customers表中ID为10001、的客户的订单信息
1 2 3 | SELECT customers.c_id, orders.o_num FROM customers INNER JOIN orders ON customers.c_id = orders.c_id AND customers.c_id = 10001; |
【例.52】在fruits表和suppliers表之间使用INNER JOIN语法进行内连接查询，并对查询结果排序
1 2 3 4 | SELECT suppliers.s_id, s_name,f_name, f_price FROM fruits INNER JOIN suppliers ON fruits.s_id = suppliers.s_id ORDER BY fruits.s_id; |
