看到好的文档,总结的很好,于是便将它按照我的理解来做了一番总结。
整体把握,先从思维导图开始:
下面来细细分解。
Select * from 表名 Select * from stuInfo
Select 字段1,字段2,字段3… from 表名 Select stuName,stuSex from stuInfo
select distinct 列名1 from 表名
Select * from score where degree between 60 and 80
select * from score where degree in (85,86,88)
select * from score where degree>=60 and degree<=80
select * from student where class='95031‘ or Ssex='女'
select * from student order by class desc
select count(*) as CNT from student where class='95031'
select max(degree) From Score
select min(degree) From score
select avg(degree) as 课程平均分 from score where cno='3-105';
select cno, avg(degree) from score where cno like'3%‘ group by cno having count(*) >5