ORDER BY alphanumeric characters only in SQLite

Question

I am sorting songs in SQLite (on Android). I want to order them:

1. Case-insensitive
2. With leading-digits at the end, by integer value.
3. Without punct

Answer 1

If you're allowed to create functions, this is what I'd create (taken from How to strip all non-alphabetic characters from string in SQL Server? and modified a bit):

Create Function [dbo].[RemoveNonAlphaNumericCharacters](@Temp VarChar(1000))
Returns VarChar(1000)
AS
Begin

    Declare @KeepValues as varchar(50)
    Set @KeepValues = '%[^a-zA-Z0-9\s]%'
    While PatIndex(@KeepValues, @Temp) > 0
        Set @Temp = Stuff(@Temp, PatIndex(@KeepValues, @Temp), 1, '')

    Return @Temp
End

This would meet your #3 requirement and strip all the junk out of your string, then your query would look like this:

SELECT n
FROM songs
ORDER BY
  CASE WHEN [dbo].[RemoveNonAlphaNumericCharacters](name) GLOB '[0-9]*' THEN 1
       ELSE 0
  END,
  CASE WHEN [dbo].[RemoveNonAlphaNumericCharacters](name) GLOB '[0-9]*' THEN CAST(name AS INT)
       ELSE [dbo].[RemoveNonAlphaNumericCharacters](name)
  END
COLLATE NOCASE

It doesn't look pretty and might not have best performance. I'd probably do, what Stefan suggested. Parse your song names and insert trimmed ones into a separate column just for ordering (And of course have index on that column). It should be best solution.