交集并集差集

1、
--内连接
select   *  from  Student a inner  join SC b
on a.Sno=b.Sno

---左连接
select   *  from  Student a left join SC b
on a.Sno=b.Sno

----差集
select   sno  from  Student
except 
 select   sno  from SC  
 
 ---交集
 select   sno  from  Student
intersect 
 select   sno  from SC  
 
 ---并集
 select   sno  from  Student
union 
 select   sno  from SC  
============================ 
 ---两个金额之间的区间(开始金额为1，结束金额7)
---BMoney和EMoney查询值，1和7是赋值
 (BMoney>='1' and (BMoney<='7' or EMoney<='7' ))
 or
 (BMoney<='1' and EMoney>='1')


------
----sql求两金额区间

go 
use  Test

declare @b int
declare @e int
declare @b1 int
declare @e1 int
set @b=2
set @e=8
set @b1=1.8
set @e1=11
if( (@b>=@b1 and (@b<=@e1 or @e<=@e1))
   or (@b<=@b1 and @e>=@b1)
   )
   begin
       print '在区间内'
   end
else
   begin
      print '不在区间内';
   end
go
交集并集差集

悦读
