HiI done like this....correct me if iam in wrongSELECT D_Part_No, STDEV(Val)AS STD_DEVFROM (SELECT D_Part_No , D_PERIOD_1 , D_PERIOD_2 , D_PERIOD_3 , D_PERIOD_4 , D_PERIOD_5 , D_PERIOD_6 , D_PERIOD_7 , D_PERIOD_8 , D_PERIOD_9 , D_PERIOD_10, D_PERIOD_11, D_PERIOD_12 FROM DBO.INV_DEMAND_DATA(NOLOCK) WHERE D_User_Id = 2890541 ) p UNPIVOT (Val FOR Period IN( D_PERIOD_1 , D_PERIOD_2 , D_PERIOD_3 , D_PERIOD_4 , D_PERIOD_5 , D_PERIOD_6 , D_PERIOD_7 , D_PERIOD_8 , D_PERIOD_9 , D_PERIOD_10, D_PERIOD_11, D_PERIOD_12 ) )AS unpvtGROUP BY D_Part_No
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