Question

Quick check to see if anyone has or knows of a T-SQL function capable of generating slugs from a given nvarchar input. i.e;

“Hello World” > “hello-world”
“This is a test” > “this-is-a-test”

I have a C# function that I normally use for these purposes, but in this case I have a large amount of data to parse and turn into slugs, so it makes more sense to do it on the SQL Server rather than have to transfer data over the wire.

As an aside, I don’t have Remote Desktop access to the box so I can’t run code (.net, Powershell etc) against it

Thanks in advance.

EDIT:
As per request, here’s the function I generally use to generate slugs:

public static string GenerateSlug(string n, int maxLength)
{
    string s = n.ToLower();                
    s = Regex.Replace(s, @"[^a-z0-9s-]", "");              
    s = Regex.Replace(s, @"[s-]+", " ").Trim();             
    s = s.Substring(0, s.Length <= maxLength ? s.Length : maxLength).Trim();             
    s = Regex.Replace(s, @"s", "-"); 
    return s;
}

Answer 1

This is what I’ve come up with as a solution. Feel free to fix / modify where needed.

I should mention that the database I’m currently developing against is case insensitive hence the LOWER(@str).

CREATE FUNCTION [dbo].[UDF_GenerateSlug]
(   
    @str VARCHAR(100)
)
RETURNS VARCHAR(100)
AS
BEGIN
DECLARE @IncorrectCharLoc SMALLINT
SET @str = LOWER(@str)
SET @IncorrectCharLoc = PATINDEX('%[^0-9a-z ]%',@str)
WHILE @IncorrectCharLoc > 0
BEGIN
SET @str = STUFF(@str,@incorrectCharLoc,1,'')
SET @IncorrectCharLoc = PATINDEX('%[^0-9a-z ]%',@str)
END
SET @str = REPLACE(@str,' ','-')
RETURN @str
END

Mention to: http://blog.sqlauthority.com/2007/05/13/sql-server-udf-function-to-parse-alphanumeric-characters-from-string/ for the original code.