Database

select @MinDate = min(TheDate) from tDate where TheDate > convert(datetime,'01-01-1980',105)
select @MaxDate = max(TheDate) from tDate


--The following statements are not doing anything meaningful, I believe.

set @Year = datepart(yyyy,@MinDate)
set @Month = datepart(mm,@MinDate)
set @Day = datepart(d,@MinDate)

if len(@Month) = 1
begin
  set @Month = '0'+@Month
end

if len(@Day) = 1
begin
  set @Day = '0'+@Day
end

set @MinDate = convert(datetime,@Day+'-'+@Month+'-'+@Year,105)

set @Year = datepart(yyyy,@MaxDate)
set @Month = datepart(mm,@MaxDate)
set @Day = datepart(d,@MaxDate)

if len(@Month) = 1
begin
  set @Month = '0'+@Month
end

if len(@Day) = 1
begin
  set @Day = '0'+@Day
end

set @MaxDate = convert(datetime,@Day+'-'+@Month+'-'+@Year,105)