SET @ZDAY = DATEDIFF(DAY,@FDATE,@ZDATE)

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SQL-Server-2008R2

Will the above codes give the number of days between 2 dates?

I have a stored procedure which is not running because it "Times out" and this code

was the latest to be introduced

SET @FDATE   =  DATEADD(DAY,@FDAY-1,DATEADD(MONTH,@CMTH-1,DATEADD(YEAR,@CYR-1900,0)))


                            IF @CCMTH = 12
                              BEGIN
                              SET @CCMTH = 1
                              SET @CCYR  = @CCYR+1
                              END
                            ELSE
                              IF  @CCMTH <> 12
                              BEGIN
                              SET @CCMTH =@CCMTH+1
                              SET @CCYR  =@CCYR
                              END
                SET @ZDATE   =  DATEADD(DAY,@FDAY-1,DATEADD(MONTH,@CCMTH-1,DATEADD(YEAR,@CCYR-1900,0)))


                SET @ZDAY    =  DATEDIFF(DAY,@FDATE,@ZDATE)