--计算这个月的第一天create FUNCTION fnFirstDateOfMonth( @dtmDate datetime ) returns datetimeasbegin declare @inyDay tinyint declare @dtmDateNew datetime set @inyDay = day(@dtmDate)
set @dtmDateNew = dateadd(day, -@inyday+ 1, @dtmDate) return (@dtmDateNew)
set @dtmDateNew = dateadd(day, -@inyday+ 1, @dtmDate) return (@dtmDateNew)
set @dtmDateNew = dateadd(day, -@inyday+ 1, @dtmDate) return (@dtmDateNew)END