From e335d8f5d418b5b1795079afa409d6951cf3a6aa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=AE=98=E6=96=87=E8=AF=9A?= <3287861587@qq.com>
Date: Mon, 13 Mar 2023 23:27:57 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BD=9C=E4=B8=9A?=
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---
 .../20230112.md"                              | 124 ++++++++++++++++++
 1 file changed, 124 insertions(+)
 create mode 100644 "08 \345\256\230\346\226\207\350\257\232/20230112.md"

diff --git "a/08 \345\256\230\346\226\207\350\257\232/20230112.md" "b/08 \345\256\230\346\226\207\350\257\232/20230112.md"
new file mode 100644
index 0000000..72f5c66
--- /dev/null
+++ "b/08 \345\256\230\346\226\207\350\257\232/20230112.md"	
@@ -0,0 +1,124 @@
+~~~ mysql
+-- 图片所给的数据进行数据表的建立和数据插入，然后进行以下查询操作
+CREATE DATABASE sb charset utf8;
+use sb;
+
+CREATE TABLE xm(
+stuno VARCHAR(20),
+stuname VARCHAR(20),
+stuage INT,
+stuaddress VARCHAR(20),
+stuseat INT,
+stusex INT
+);
+CREATE TABLE cj(
+examno INT,
+stuno VARCHAR(20),
+writtenexam int,
+labexam INT
+);
+
+INSERT into xm VALUES
+('s2501','张秋利',20,'美国硅谷',1,1),
+('s2502','李斯文',18,'湖北武汉',2,0),
+('s2503','马文才',22,'湖南长沙',3,1),
+('s2504','欧阳俊雄',21,'湖北武汉',4,0),
+('s2505','梅超风',20,'湖北武汉',5,1),
+('s2506','陈旋风',19,'美国硅谷',6,1),
+('s2507','陈风',20,'美国硅谷',7,0);
+
+INSERT into cj VALUES
+(1,'s2501',50,70),
+(2,'s2502',60,65),
+(3,'s2503',86,85),
+(4,'s2504',40,80),
+(5,'s2505',70,90),
+(6,'s2506',85,90);
+
+-- 1.查询学生信息表（stuinfo）中所有列信息，给每列取上中文名称
+-- 
+SELECT stuno 学号,stuname 姓名,stuage 年龄,stuaddress 地址,stuseat 座号,stusex 性别 from stuinfo;
+-- 2.查询学生信息表（stuinfo）中的姓名，年龄和地址三列的信息
+SELECT stuname,stuage,stuaddress from stuinfo;
+-- 3.查询学生分数表（stuexam）中的学号，笔试和机试三列的信息，并为这三列取中文名字
+-- 
+SELECT stuno 学号,writtenexam 笔试,labexam 机试 from stuexam;
+-- 5.查询学生分数表（stuexam）中的学生的学号，笔试，机试以及总分这四列的信息
+-- 
+SELECT stuno,writtenexam,labexam,(writtenexam+labexam) from stuexam;
+-- 6.查询学生信息表（stuInfo）中学生来自哪几个地方 
+-- 
+SELECT stuaddress from stuinfo GROUP BY stuaddress;
+-- 7.查询学生信息表（stuInfo）中学生有哪几种年龄，并为该列取对应的中文列名
+-- 
+SELECT stuage 年龄 FROM stuinfo GROUP BY stuage;
+-- 8.查询学生信息表（stuInfo）中前3行记录 
+-- 
+SELECT * from stuinfo LIMIT 3;
+-- 9.查询学生信息表（stuInfo）中前4个学生的姓名和座位号
+-- 
+SELECT stuname,stuseat from stuinfo LIMIT 4;
+-- 11.将地址是湖北武汉，年龄是20的学生的所有信息查询出来
+-- 
+SELECT * from stuinfo where stuaddress='湖北武汉' and stuage=20;
+-- 12.将机试成绩在60-80之间的信息查询出来，并按照机试成绩降序排列
+-- 
+SELECT * from stuexam where labexam BETWEEN 60 and 80 ORDER BY labexam DESC;
+-- 13.查询来自湖北武汉或者湖南长沙的学生的所有信息
+-- 
+SELECT * from stuinfo where stuaddress in ('湖北武汉','湖南长沙');
+-- 14.查询出笔试成绩不在70-90之间的信息,并按照笔试成绩升序排列
+-- 
+SELECT * from stuexam where writtenexam not BETWEEN 70 and 90 ORDER BY writtenexam;
+-- 15.查询年龄没有写的学生所有信息
+-- 
+SELECT * from stuinfo where stuage is NULL;
+-- 16.查询年龄写了的学生所有信息
+-- 
+SELECT * from stuinfo where stuage is not NULL;
+
+-- 17.查询姓张的学生信息
+SELECT * from stuinfo where stuname like '张%';
+-- 
+-- 18.查询学生地址中有‘湖’字的信息
+-- 
+SELECT * from stuinfo where stuaddress like '%湖%';
+-- 19.查询姓张但名为一个字的学生信息
+-- 
+SELECT * from stuinfo where stuname like '张_';
+-- 20.查询姓名中第三个字为‘俊’的学生的信息，‘俊’后面有多少个字不限制
+-- 
+SELECT * from stuinfo where stuname like '__俊%';
+-- 21.按学生的年龄降序显示所有学生信息
+-- 
+SELECT * from stuinfo where stuage ORDER BY stuage desc ;
+-- 22.按学生的年龄降序和座位号升序来显示所有学生的信息
+-- 
+SELECT * from stuinfo where stuage ORDER BY stuage desc,stuseat asc
+-- 23显示笔试第一名的学生的考试号，学号，笔试成绩和机试成绩
+--
+SELECT examno,stuno,writtenexam,labexam from stuexam where writtenexam= 
+(SELECT max(writtenexam) from stuexam);
+
+-- 24.显示机试倒数第一名的学生的考试号，学号，笔试成绩和机试成绩
+-- 
+SELECT examno,stuno,writtenexam,labexam from stuexam where labexam= 
+(SELECT min(labexam) from stuexam);
+-- 25.查询每个地方的学生的平均年龄
+-- 
+SELECT stuaddress,round(avg(stuage),2) 平均年龄 from stuinfo GROUP BY stuaddress;
+-- 26.查询男女生的分别的年龄总和
+-- 
+SELECT stusex,sum(stuage) 年龄总和 from stuinfo GROUP BY stusex;
+-- 27.查询每个地方的男女生的平均年龄和年龄的总和
+SELECT stuaddress,round(avg(stuage),2) 平均年龄,sum(stuage) 年龄总和 from stuinfo GROUP BY stuaddress;
+~~~
+
+
+
+
+
+
+
+
+
-- 
Gitee