练 习

|------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| 写出sql语句，查询所有年龄大于20岁的员工 |
| | 2 | select * from employee where age>20; |
| | 3 | 写出sql语句，查询所有年龄大于等于22小于25的女性员工 |
| | 4 | select * from employee where age between 22 and 25 and sex='女'; |
| | 5 | 写出sql语句，统计男女员工各有多少名 |
| | 6 | select Sex,count(*) as count from employee group by Sex; |
| | 7 | 写出sql语句，按照年龄降序获取员工信息 |
| | 8 | select * from emloyee where age index; |
| | 9 | 写出sql语句，获取员工中哪个姓名具有重名现象 |
| | 10 | select Name,count(*) as count from employee group by Name having count>1; |
| | 11 | 写出sql语句，查询所有姓张的员工 |
| | 12 | select * from employee where Name like '张%'; |
| | 13 | 写出sql语句，查询住址为北京的前3条记录 |
| | 14 | select * from employee where Address='北京' limit 3; |
| | 15 | 写出sql语句，查询员工总数 |
| | 16 | select count(*) from employee; |
| | 17 | 写出sql语句，向表中插入一条记录 |
| | 18 | insert into employee |
| | 19 | values("周一"，"男"，"25"，"张家口"); |
| | 20 | 写出sql语句，修改员工张四的住址为南京 |
| | 21 | update employee set Address='南京' where Name='张四'; |
| | 22 | 写出sql语句，删除年龄大于24岁的女员工 |
| | 23 | delete from employee where Sex='女' and Age>24; java第二十四课. · 7719ec3 · WL---code/WL仓库 - Gitee.com |