Generate an offline minecraft UUID v3 based on the case sensitive player name

minecraft-offline-uuid.sql

CREATE OR REPLACE FUNCTION generate_offline_uuid(
    username_p VARCHAR(20)
) RETURNS VARCHAR(36) BEGIN
    DECLARE uuid_bytes VARCHAR(36);
    SELECT MD5(CONCAT('OfflinePlayer:', username_p)) INTO uuid_bytes;
    SELECT INSERT(uuid_bytes, 13, 2, HEX(CONV(SUBSTR(uuid_bytes, 13, 2), 16, 10) & 0x0f | 0x30)) INTO uuid_bytes;
    SELECT INSERT(uuid_bytes, 17, 2, HEX(CONV(SUBSTR(uuid_bytes, 17, 2), 16, 10) & 0x3f | 0x80)) INTO uuid_bytes;
    RETURN (SELECT LCASE(CONCAT_WS('-',
                             SUBSTR(uuid_bytes, 1, 8),
                             SUBSTR(uuid_bytes, 9, 4),
                             SUBSTR(uuid_bytes, 13, 4),
                             SUBSTR(uuid_bytes, 17, 4),
                             SUBSTR(uuid_bytes, 21)
                       )));
END;