MariaDB UUID_TO_BIN and BIN_TO_UUID pollyfills

mariadb-uuid-functions.sql

DELIMITER //

CREATE FUNCTION UUID_TO_BIN(u CHAR(36))
RETURNS BINARY(16)
BEGIN
  IF u IS NULL THEN
    RETURN NULL;
  END IF;
  SET u = REPLACE(u, '-', '');
  RETURN CONCAT(
    UNHEX(SUBSTR(u, 1, 8)),
    UNHEX(SUBSTR(u, 9, 4)),
    UNHEX(SUBSTR(u, 13, 4)),
    UNHEX(SUBSTR(u, 17, 4)),
    UNHEX(SUBSTR(u, 21))
  );
END//

CREATE FUNCTION BIN_TO_UUID(b BINARY(16))
RETURNS CHAR(36)
BEGIN
    IF b IS NULL THEN
        RETURN NULL;
    END IF;
    RETURN LOWER(CONCAT(
        HEX(SUBSTR(b, 1, 4)), '-',
        HEX(SUBSTR(b, 5, 2)), '-',
        HEX(SUBSTR(b, 7, 2)), '-',
        HEX(SUBSTR(b, 9, 2)), '-',
        HEX(SUBSTR(b, 11))
    ));
END//

DELIMITER ;