ibatis关键词

 isGreaterThan

<select id="getUserList" resultMap="user">

         select * from user

            <isGreaterThan prepend="and" property="id" compareValue="0">

                   where user_id = #userId#

            </isGreaterThan>

             order by createTime desc

</select>

上面的例子中，根据参数bean“id”属性的不同情况，可创建两个可能的语句。如果参数“id”大于0，将创建下面的语句：

   select * from user where user_id = ?  order by createTime desc

或者，如果“id”参数小于等于0，将创建下面的语句：

   select * from user  order by createTime desc

isEqual

<isEqual property="state" compareValue="0">

</isEqual>

或

<isEqual property="state" compareProperty="nextState">

</isEqual>

 动态ORDER
BY

<dynamic prepend="ORDER BY">

   <isNotEmpty property="order">

    $order$ $sortDirection$

   </isNotEmpty>

  </dynamic>

例子：

<select id="getNewsList" resultMap="newsResult" parameterClass="map">

select NEWS_ID,BLOCK_ID,NEWS_TITLE,NEWS_CONTENT,NEWS_SECONDTITLE,NEWS_SUMMARY,NEWS_AUTHOR,NEWS_SOURCE,NEWS_ANNEX,NEWS_TIME,NEWS_OPEN,NEWS_KEYWORDS,NEWS_APPROVE,ISTOP,BROWSENUM,NEWS_COMMENT,NEWS_REFUSE,NEWS_AUDITOR,lasteditor,prjid,prjname,wsflag,MEM_NAME,LASTEDITTIME,ISBLOCKPIC 

from yc_news 

where BLOCK_ID = #blockid#

  <dynamic prepend="ORDER BY">

   <isNotEmpty property="orderstr">

     $orderstr$

   </isNotEmpty>

  </dynamic>

 </select>

查询时间段

<isNotEmpty property="startTime" prepend=" and ">  

    f.Time >= #startTime#  

</isNotEmpty>  

<isNotEmpty property="endTime" prepend=" and ">  

    <![CDATA[  

    f.Time <= #endTime#  

    ]]>  

</isNotEmpty>