ALTER FUNCTION [dbo].[fn_MyRound] ( @val DECIMAL(20,10), @len INT=2, @myindex int=4 ) RETURNS float AS BEGIN while @myindex>@len BEGIN set @myindex=@myindex-1 set @val=round(@val,@myindex) end RETURN CONVERT(float, @val) END
原文：http://www.cnblogs.com/ilookbo/p/4957656.html