SQL效率有关问题

SQL效率问题

SQL code

Declare @CurrentID int, @JobCode char(10),@Date char(10),@Time char(4)    BEGIN TRY        SET @CurrentID = 1;        Select @JobCode = JobCode,@Date = [Date],@Time = [Time]           from Atd_DataReceive        where DataReceiveId = @CurrentID;                WHILE (@@ROWCOUNT >= 1)        BEGIN           UPDATE Atd_DayResult           SET Time1 = @Time           WHERE JobCode = @JobCode AND AtdDate = @Date        SET @CurrentID = @CurrentID + 1;         SELECT @JobCode = JobCode,@Date = [Date],@Time = [Time]        from Atd_DataReceive        WHERE DataReceiveId = @CurrentID;                         END        COMMIT TRANSACTION    END TRY

SQL code

update a  SET Time1=b.[Time] from Atd_DayResult a,Atd_DataReceive bwhere a.JobCode =b.JobCode and a.[Date]=b.[Date]