Question

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How to compare software versions using SQL Server?

I am a complete and utterly new to sql, but today I found an error in a sql query here at work that is very important. So I could use some help:

Given an sql string that represents a product version

‘15.0.0.0’

is there a foolproof way to sort or compare that string similar to how .NET class System.Version compares instances?

So, given such a hypothetical construct, or function or what-ever, I would expect that ‘15.5.568’ would be greater than ‘15.0.0.0’.

Thanks

Answer 1

Assuming SQL Server, and a known maximum number of parts, here’s a user defined function that does the same as parsename, but works on any number of parts:

Create Function dbo.VersionNthPart(@version as nvarchar(max), @part as int) returns int as
Begin

  Declare
    @ret as int = null,
    @start as int = 1,
    @end as int = 0,
    @partsFound as int = 0

  if @version is not null
  Begin
    Set @ret = 0
    while @partsFound < @part
    Begin
      Set @end = charindex('.', @version, @start)
      If @end = 0
        Set @partsFound = @part -- bail early
      else
      Begin
        Set @partsFound = @partsFound + 1
        If @partsFound = @part
          Set @ret = Convert(int, substring(@version, @start, @end - @start))
        Else
          Set @start = @end + 1
      End
    End
  End
  return @ret
End

Example Usage:

With
  tmp
As (
    Select '1.0.0.5' As Version
    Union All Select '1.5.0.06'
    Union All Select '1.0.0.06'
    Union All Select '2.0.0.0'
    Union All Select '2.0.1.1'
    Union All Select '15.5.568'
    Union All Select '15.0.0.0'
    Union All Select '15.15.1323.22'
    Union All Select '15.15.622.55'
)

Select
  *
From
   tmp
Order By
  dbo.VersionNthPart(Version, 1),
  dbo.VersionNthPart(Version, 2),
  dbo.VersionNthPart(Version, 3),
  dbo.VersionNthPart(Version, 4)

http://sqlfiddle.com/#!3/e942b/3