SQL exists( select 1 from

use UnlockIndustry

select * from Info_Coordinate as A
join Info_Employee on A.EmployeeId=Info_Employee.EmployeeId
Where exists( select 1 from ( select EmployeeId,MAX(CreateTime) as CreateTime from Info_Coordinate  group by Info_Coordinate.EmployeeId ) as b
where A.EmployeeId=b.EmployeeId and A.CreateTime=b.CreateTime)
And Info_Employee.CompanyId='1306010001'
/*
关联人员和地址表。  select * from info_A as A JOIN Info_B ON A.id=Info_B.id where exists() and info_B.Cid=''
*/

use MyMvc
select * from Info_Company
select * from Info_Empoyee
select * from Info_Empoyee left Join Info_Company on Info_Empoyee.CompanyID=Info_Company.CompanyID
select * from Info_Empoyee where exists(select 1 from Info_Company where Info_Empoyee.CompanyId=Info_Company.CompanyID)