DECLARE
    l_xml            sys.xmltype;
    l_amount         BINARY_INTEGER := 32000;
    l_buffer         RAW(32000);
    l_pos            INTEGER := 1;
    l_stage          NUMBER;
    content          CLOB;
    content_blob     BLOB;
    content_length   NUMBER;
BEGIN
    SELECT
        xml_data
    INTO l_xml
    FROM
        xxln_vs_publish_stg
    WHERE
        xml_data IS NOT NULL
        AND ROWNUM < 2;

    content := xmltype.getclobval(l_xml);
    xxln.convert_clob_to_blob(content, content_blob);
    content_length := dbms_lob.getlength(content_blob);
    dbms_output.put_line(content_length);
    apex_json.initialize_clob_output;
    IF dbms_lob.getlength(content_blob) < 32000 THEN
        apex_json.write(content);
    ELSE
        WHILE l_pos < content_length--DBMS_LOB.GETLENGTH(v_output_file_blob)
         LOOP
            dbms_lob.read(content_blob, l_amount, l_pos, l_buffer);
            apex_json.write(content);
            l_pos := l_pos + l_amount;
        END LOOP;
    END IF;

    dbms_output.put_line(apex_json.get_clob_output);
    apex_json.free_output;
END;