SQL Server里 函数 的两种用法(可以代替游标) 1. 因为update里不能用存储过程,然而要根据更新表的某些字段还要进行计算。我们常常采用游标的方法,这里用 函数 的方法实现。 函数 部分: 以下是引用片段: CREATEFUNCTION[DBO].[FUN_GETTIME](@TASKPHASEIDI
SQL Server里函数的两种用法(可以代替游标)
1. 因为update里不能用存储过程,然而要根据更新表的某些字段还要进行计算。我们常常采用游标的方法,这里用函数的方法实现。
函数部分:
以下是引用片段: CREATE FUNCTION [DBO].[FUN_GETTIME] (@TASKPHASEID INT) RETURNS FLOAT AS BEGIN DECLARE @TASKID INT, @HOUR FLOAT, @PERCENT FLOAT, @RETURN FLOAT IF @TASKPHASEID IS NULL BEGIN RETURN(0.0) END SELECT @TASKID=TASKID,@PERCENT=ISNULL(WORKPERCENT,0)/100 FROM TABLETASKPHASE WHERE ID=@TASKPHASEID SELECT @HOUR=ISNULL(TASKTIME,0) FROM TABLETASK WHERE ID=@TASKID SET @RETURN=@HOUR*@PERCENT RETURN (@RETURN) END |
调用函数的存储过程部分
以下是引用片段: CREATE PROCEDURE [DBO].[PROC_CALCCA] @ROID INT AS BEGIN DECLARE @CA FLOAT UPDATE TABLEFMECA SET Cvalue_M= ISNULL(MODERATE,0)*ISNULL(FMERATE,0)*ISNULL(B.BASFAILURERATE,0)*[DBO].[FUN_GETTIME](C.ID) FROM TABLEFMECA ,TABLERELATION B,TABLETASKPHASE C WHERE ROID=@ROID AND TASKPHASEID=C.ID AND B.ID=@ROID SELECT @CA=SUM(ISNULL(Cvalue_M,0)) FROM TABLEFMECA WHERE ROID=@ROID UPDATE TABLERELATION SET CRITICALITY=@CA WHERE ID=@ROID END GO |

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