mySQL Stored Function to create a slug

Question

Is there a mysql stored function out there to create a slug from a url (or any value really).

So my query can be:

SELECT *, SLUG(url) FROM clients

Answer 1

My two cents:

CREATE FUNCTION slugify(str VARCHAR(255))
  RETURNS VARCHAR(255)
  LANGUAGE SQL
  DETERMINISTIC
  NO SQL
  SQL SECURITY INVOKER
BEGIN
    DECLARE slug, allowed_chars VARCHAR(255);
    DECLARE current_char VARCHAR(1);
    DECLARE pos, len INT;

    -- Add here custom replaces
    SET slug = REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(LOWER(TRIM(str)), 'ú', 'u'), 'ç', 'c'), 'ğ', 'g'), ' ', '-'), 'é', 'e'), 'è', 'e'), 'ë', 'e'), 'í', 'i'), 'î', 'i'), 'ò', 'o'), 'õ', 'o'), 'ù', 'u'), 'â', 'a'), 'ã', 'a'), 'ö', 'o'), 'ş', 's'), 'ì', 'i'), 'æ', 'ae'), 'à', 'a'), 'ê', 'e'), 'ñ', 'n'), 'ý', 'y'), 'ô', 'o'), 'û', 'u'), 'ï', 'i'), 'ó', 'o'), 'ü', 'u'), 'á', 'a'), 'å', 'a'), 'ä', 'a'), '_', '-');
    SET pos = 1;
    SET len = CHAR_LENGTH(slug);
    SET allowed_chars = 'abcdefghijklmnopqrstuvwxyz0123456789-';

    -- Remove not allowed characters
    WHILE pos <= len DO
        SET current_char = SUBSTRING(slug, pos, 1);
        IF LOCATE(current_char, allowed_chars) = 0 THEN
            SET slug = REPLACE(slug, current_char, '');
        END IF;
        SET pos = pos + 1;
    END WHILE;
    
    -- Squish dashes
    WHILE LOCATE('--', slug) > 0 DO
        SET slug = REPLACE(slug, '--', '-');
    END WHILE;
    
    RETURN slug;
END;