• 设为首页
  • 点击收藏
  • 手机版
    手机扫一扫访问
    迪恩网络手机版
  • 关注官方公众号
    微信扫一扫关注
    公众号

MySQL子查询操作实例详解

原作者: [db:作者] 来自: [db:来源] 收藏 邀请

本文实例总结了MySQL子查询操作。分享给大家供大家参考,具体如下:

定义两个表tb1和tb2

CREATE table tbl1 ( num1 INT NOT NULL);
CREATE table tbl2 ( num2 INT NOT NULL);

向两个表中插入数据:

INSERT INTO tbl1 values(1), (5), (13), (27);
INSERT INTO tbl2 values(6), (14), (11), (20);

any some关键字的子查询

SELECT num1
FROM tbl1
WHERE num1 > ANY (SELECT num2 FROM tbl2);

all关键字的子查询

SELECT num1
FROM tbl1
WHERE num1 > ALL (SELECT num2 FROM tbl2);

exists关键字的子查询

SELECT * from fruits
WHERE EXISTS
(SELECT s_name FROM suppliers WHERE s_id = 107);

SELECT * from fruits
WHERE f_price>10.20 AND EXISTS
(SELECT s_name FROM suppliers WHERE s_id = 107);

SELECT * from fruits
WHERE NOT EXISTS
(SELECT s_name FROM suppliers WHERE s_id = 107);

in关键字的子查询

SELECT c_id
FROM orders
WHERE o_num IN (SELECT o_num FROM orderitems WHERE f_id = 'c0');

SELECT c_id
FROM orders
WHERE o_num NOT IN (SELECT o_num FROM orderitems WHERE f_id = 'c0');

带比较运算符的子查询

SELECT s_id, f_name FROM fruits
WHERE s_id =
(SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');

<>所有非

SELECT s_id, f_name FROM fruits
WHERE s_id <>
(SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');

定义两个表tb1和tb2

CREATE table tbl1 ( num1 INT NOT NULL);
CREATE table tbl2 ( num2 INT NOT NULL);

向两个表中插入数据

INSERT INTO tbl1 values(1), (5), (13), (27);
INSERT INTO tbl2 values(6), (14), (11), (20);

【例.53】返回tbl2表的所有 num2 列,然后将 tbl1 中的 num1 的值与之进行比较,只要大于 num2的任何值为符合查询条件的结果

SELECT num1
FROM tbl1
WHERE num1 > ANY (SELECT num2 FROM tbl2);

【例.54】返回tbl1表的中比tbl2表num2 列所有值都大的值

SELECT num1
FROM tbl1
WHERE num1 > ALL (SELECT num2 FROM tbl2);

【例.55】查询表suppliers表中是否存在s_id=107的供应商,如果存在则查询fruits表中的记录

SELECT * from fruits
WHERE EXISTS
(SELECT s_name FROM suppliers WHERE s_id = 107);

【例.56】查询表suppliers表中是否存在s_id=107的供应商,如果存在则查询fruits表中的f_price大于10.20的记录

SELECT * from fruits
WHERE f_price>10.20 AND EXISTS
(SELECT s_name FROM suppliers WHERE s_id = 107);

【例.57】查询表suppliers表中是否存在s_id=107的供应商,如果不存在则查询fruits表中的记录

SELECT * from fruits
WHERE NOT EXISTS
(SELECT s_name FROM suppliers WHERE s_id = 107);

【例.58】在orderitems表中查询订购f_id为c0的订单号,并根据订单号查询具有订单号的客户c_id

SELECT c_id FROM orders WHERE o_num IN
(SELECT o_num FROM orderitems WHERE f_id = 'c0');

【例.59】与前一个例子语句类似,但是在SELECT语句中使用NOT IN操作符

SELECT c_id FROM orders WHERE o_num NOT IN
(SELECT o_num FROM orderitems WHERE f_id = 'c0');

【例.60】在suppliers表中查询s_city等于Tianjin的供应商s_id,然后在fruits表中查询所有该供应商提供的水果的种类

SELECT s_id, f_name FROM fruits
WHERE s_id =
(SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');

【例.61】在suppliers表中查询s_city等于Tianjin的供应商s_id,然后在fruits表中查询所有非该供应商提供的水果的种类,SQL语句如下:

SELECT s_id, f_name FROM fruits
WHERE s_id <>
(SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');

更多关于MySQL相关内容感兴趣的读者可查看本站专题:《MySQL常用函数大汇总》、《MySQL日志操作技巧大全》、《MySQL事务操作技巧汇总》、《MySQL存储过程技巧大全》及《MySQL数据库锁相关技巧汇总

希望本文所述对大家MySQL数据库计有所帮助。


鲜花

握手

雷人

路过

鸡蛋
该文章已有0人参与评论

请发表评论

全部评论

专题导读
上一篇:
MySQL连接查询实例详解发布时间:2022-02-08
下一篇:
MySQL Union合并查询数据及表别名、字段别名用法分析发布时间:2022-02-08
热门推荐
热门话题
阅读排行榜

扫描微信二维码

查看手机版网站

随时了解更新最新资讯

139-2527-9053

在线客服(服务时间 9:00~18:00)

在线QQ客服
地址:深圳市南山区西丽大学城创智工业园
电邮:jeky_zhao#qq.com
移动电话:139-2527-9053

Powered by 互联科技 X3.4© 2001-2213 极客世界.|Sitemap