mysql例子

Posted 2021-01-10 kanglun

 1 1、1. 建一张学生表 包含（ id ， name ， age ， sex ）
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 3 2. 增加四条数据 
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 5 3. 查询表中 sex 为男的数据 
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 7 4. 删除 id =3 的数据， 
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 9 5. 将 sex 为女的，修改为男
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13     create table students(id int,
14                          name varchar(20),
15                          age int,
16                          sex varchar(4));
17                          
18     insert into students values(1, "小白", 18, "男"),
19                             (2, "小张", 19, "男"),
20                             (3, "小红", 20, "女"),
21                             (4, "小泼", 21, "女");
22                             
23     select * from students where sex = "男";                        
24     
25     delete from students where id = 3;
26     
27     update students set sex = "男" where sex = "女";
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