if (ph.getLsn() > -1 && requiresRedo(loggable, page)) {
if (ph.getLsn() != Page.NO_PAGE && requiresRedo(loggable, page)) {
	protected void redoRemoveOverflow(RemoveOverflowLoggable loggable) {		try {			Page page = getPage(loggable.pageNum);            page.read();			PageHeader ph = page.getPageHeader();			if (ph.getLsn() > -1 && requiresRedo(loggable, page)) {				unlinkPages(page);			}		} catch (IOException e) {			LOG.warn("Failed to undo " + loggable.dump() + ": "					+ e.getMessage(), e);		}	}