MySQL Query Error: SELECT BS.*, B.LIST_PAGE_URL, B.SECTION_PAGE_URL, B.IBLOCK_TYPE_ID, B.CODE as IBLOCK_CODE, B.XML_ID as IBLOCK_EXTERNAL_ID, BS.XML_ID as EXTERNAL_ID FROM b_iblock_section M, b_iblock_section BS, b_iblock B WHERE M.ID=314 AND M.IBLOCK_ID=31 AND M.IBLOCK_ID=BS.IBLOCK_ID AND B.ID=BS.IBLOCK_ID AND M.LEFT_MARGIN>=BS.LEFT_MARGIN AND M.RIGHT_MARGIN<=BS.RIGHT_MARGIN ORDER BY BS.LEFT_MARGIN [MySQL server has gone away]