蝙蝠岛资源网 Design By www.hbtsch.com

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。

标签:
MySQL,子查询

蝙蝠岛资源网 Design By www.hbtsch.com
广告合作:本站广告合作请联系QQ:858582 申请时备注:广告合作(否则不回)
免责声明:本站文章均来自网站采集或用户投稿,网站不提供任何软件下载或自行开发的软件! 如有用户或公司发现本站内容信息存在侵权行为,请邮件告知! 858582#qq.com
蝙蝠岛资源网 Design By www.hbtsch.com

评论“MySQL子查询操作实例详解”

暂无MySQL子查询操作实例详解的评论...

稳了!魔兽国服回归的3条重磅消息!官宣时间再确认!

昨天有一位朋友在大神群里分享,自己亚服账号被封号之后居然弹出了国服的封号信息对话框。

这里面让他访问的是一个国服的战网网址,com.cn和后面的zh都非常明白地表明这就是国服战网。

而他在复制这个网址并且进行登录之后,确实是网易的网址,也就是我们熟悉的停服之后国服发布的暴雪游戏产品运营到期开放退款的说明。这是一件比较奇怪的事情,因为以前都没有出现这样的情况,现在突然提示跳转到国服战网的网址,是不是说明了简体中文客户端已经开始进行更新了呢?