在写sql的时候显示系统错误sql语句是这样

{php $query=urlencode('select * from dr_1_course where catid='.$catid.' AND site=2 ORDER BY updatetime desc limit=1');}
{sql sql='$query'}
{$t.site}
<div class="uk-container-center" style="background: none;">
   <!--最新动态内容开始-->
   <div class="uk-grid uk-grid-collapse">
       <div class="uk-width-1-1">
           <div class="detail-summary">
               <div class="detail-title">
                   <a title="">{$t.title}</a>
               </div>
               <div class="detail-content" style="margin-top: 20px;margin-bottom: 0px">
                   {module module=course join=1_course_data_0 on=id id=$t.id return=r}
                   {$r.content}
                   {/module}
               </div>
           </div>
       </div>
   </div>
</div>
<!--课程列表结束-->
</div>
{/sql}