织梦dedecms禁止发布标题重复的文档的办法

if(empty($click)) $click = ($cfg_arc_click=='-1' ? mt_rand(50, 200) : $cfg_arc_click); 

 $row = $dsql->GetOne("Select * From `wmd_archives` where title like '$title' ");
        if(is_array($row))
        {
            ShowMsg("对不起，请不要发布重复文档！","-1");
            exit();
        }