UPDATE p_block_instances
       SET defaultregion = :o_newdefaultregion
     WHERE id IN (
        SELECT * FROM (
            SELECT bi.id
              FROM p_my_pages mp
              JOIN p_block_instances bi
                    ON bi.blockname = :o_blockname
                   AND bi.pagetypepattern = :o_pagetypepattern
                   AND  CAST(bi.subpagepattern AS INT)  = mp.id
             WHERE mp.private = 1
               AND mp.name = :o_pagename
               AND bi.defaultregion <> :o_existingnewdefaultregion
               AND bi.subpagepattern IS NOT NULL
               AND NOT bi.subpagepattern = ' '
        ) bid
)