sql 存儲過程參數為空則不作為條件

select DocDetailedNo,CombinedCode,a.ProjectName,DocOperCode,a.PatientID,a.CreateTime,a.ExecutiveDepName ,a.ExecutiveDepNo ,
from ApplyInfo a
left join ApplyAfterDealInfo ap on a.DocDetailedNo=ap.AppFormNo
where 1=1
and a.DocOperCode<>'CA'
and a.ExecutiveDepNo = @DepNo
and ap.StudyStatus<>'3'
and ap.StudyStatus<>'2'
and Convert(char(10),a.CreateTime,120) between @time and @timeEnd
and (a.PatientID in(@Backup2) OR @Backup2='')

以上這種寫法可不需要拼接字符串方式 動態處理參數值為空時不作為 篩選條件