聯盟在SQL Server 2005

Question

以下是我的查詢

Select vehicleID from trip where (StartingDate between ''+ convert(varchar(10), @StartDate,111) +'' and ''+ convert(varchar(10), @EndDate,111)+'') 
or (enddate between ''+ convert(varchar(10), @StartDate,111) +'' and ''+ convert(varchar(10), @EndDate,111)+'') 
or(StartingDate <= @StartDate and enddate >= @EndDate) 
UNION 
Select vehicleID from VehicleMaintenance where (FromDate between ''+ convert(varchar(10), @StartDate,111) +'' and ''+ convert(varchar(10), @EndDate,111)+'') 
or (todate between ''+ convert(varchar(10), @StartDate,111) +'' and ''+ convert(varchar(10), @EndDate,111)+'') 
or (FromDate <= @StartDate and todate >= @EndDate) 
) as vehicle 

如何選擇從上面的查詢結果不同vehicleId ....

Answer 1

注意UNION將刪除重複項（而UNION ALL不會） ，所以你應該已經有唯一的車輛ID