SELECT co.client${IF(LEN(wtd) == 0,""," ,CASE WHEN a.WorkSheetTypeDisplay = '搬运' THEN IIF((a.WorkSheetType & 761907)> 0,IIF(a.RealWeight>=ISNULL(a.RealKGS,0),a.RealWeight,ISNULL(a.RealKGS,0)),0) ELSE 0 END AS weight")}FROM dbo.DWD_ORDERS aJOIN (SELECT WorkSheetCode,IIF(yuanshi IS NULL ,IIF(yincang IS NULL,ClientForShort,yincang),yuanshi ) AS clientFROM dbo.ClientRealOrNot ) co ON a.WorkSheetCode = co.WorkSheetCode求问,如上述语句所示,我想当 wtd 这个参数为搬运的时候展示client和weight 这个字段,wtd 为推运的时候展示client和height这个字段,需要怎么写