在ibatis的sql语句xml配置文件中,写sql语句会经常用到大于等于小于等于等等符号。网上搜罗了一些写法,大致有3种:

  1. 其实就是xml特殊符号,转义的方式。 
    &lt; < 
    &gt; > 
    &lt;&gt; <> 
    &amp; & 
    &apos; ’ 
    &quot; ” 
    比如: 
    select (case when (UNIX_TIMESTAMP(now())-UNIX_TIMESTAMP(ur.offline_time)-5*60*1000)&gt;0 then '1' else '0' end) as offline_flag from ……

  2. 使用<![CDATA[ sql语句]]>符号进行说明,将此类符号不进行解析 。 
    比如: 
    <isEqual property="offline_flag" compareValue="0"> 
    and <![CDATA[((UNIX_TIMESTAMP(now())-UNIX_TIMESTAMP(ur.offline_time)-5*60*1000)<=0 or u.record_id=0)]]> 
    </isEqual>

  3. 如果是参数字段,可以用ibatis的语法。 
    <isEqual> 相等。 
    <isNotEqual> 不等。 
    <isGreaterThan> 大于 
    <isGreaterEqual> 大于等于 
    <isLessThan> 小于 
    <isLessEqual> 小于等于
     
    比如: 
    <isNotEmpty prepend="AND" property="username"> 
    u.username like '%$username$%' 
    </isNotEmpty> 
    <isNotEmpty prepend="AND" property="location"> 
    concat(u.country,u.province,u.city) like '%$location$%' 
    </isNotEmpty> 
    <isEqual property="offline_flag" compareValue="1"> 
    and (UNIX_TIMESTAMP(now())-UNIX_TIMESTAMP(ur.offline_time)-5*60*1000)&gt;0 
    </isEqual> 
    <isEqual property="offline_flag" compareValue="0"> 
    and <![CDATA[((UNIX_TIMESTAMP(now())-UNIX_TIMESTAMP(ur.offline_time)-5*60*1000)<=0 or u.record_id=0)]]> 
    </isEqual> 
    <!-- sort --> 
    <isEqual property="sort_onlinetime" compareValue="asc"> 
    order by u.online_time asc 
    </isEqual> 
    <isEqual property="sort_onlinetime" compareValue="desc"> 
    order by u.online_time desc 
    </isEqual> 
    <isEqual property="sort_registtime" compareValue="asc"> 
    order by u.register_time asc 
    </isEqual> 
    <isEqual property="sort_registtime" compareValue="desc"> 
    order by u.register_time desc 
    </isEqual> 
    <isEqual property="sort_appversion" compareValue="asc"> 
    order by u.app_version asc 
    </isEqual> 
    <isEqual property="sort_appversion" compareValue="desc"> 
    order by u.app_version desc 
    </isEqual>

 
 
05-11 14:47