ibatis dynamic标签 的使用

<!-- 根据给定的参数查询出对应的对账日志记录 -->
    <select id="listByParamMap" parameterClass="java.util.Map" resultClass="AccCheckLog">
        select rl.ID as id,
               rl.STAFF_ID as staffId,
               rl.STAFF_NAME as staffName,
               rl.STAFF_PHONE_NUM as staffPhoneNum,
               rl.ORDER_ID as orderId,
               rl.AWARD_DATE as awardDate,
               rl.PAY_AMOUNT as payAmount,
               rl.ISSUER_ID as issuerId,
               rl.APPFROM as appfrom,
               rl.ISSUER_NAME as issuerName,
               rl.LOG_TIME as logTime,
               rl.TYPE as type,
               rl.COMMENTS as comments,
               rl.CHECK_RESULT_CODE as checkResultCode
          from INFO_AWARD_COUPON_RECORD_LOG rl
          <dynamic prepend="where">
                <isNotNull property="appfrom" prepend="and">
                        rl.APPFROM = #appfrom#
                </isNotNull>
                <isNotNull property="staffId" prepend="and">
                        rl.STAFF_ID = #staffId#
                </isNotNull>
                <isNotNull property="orderId" prepend="and">
                        rl.ORDER_ID = #orderId#
                </isNotNull>
                <isNotNull property="logTimeStart" prepend="and">
                        <![CDATA[rl.LOG_TIME >= to_date(#logTimeStart#,'yyyymmdd')]]>
                </isNotNull>
                <isNotNull property="logTimeEnd" prepend="and">
                        <![CDATA[rl.LOG_TIME <= to_date(#logTimeEnd#,'yyyymmdd')]]>
                </isNotNull>
                <isNotNull property="checkResultCode" prepend="and">
                        rl.CHECK_RESULT_CODE = #checkResultCode#
                </isNotNull>
                <isNotNull property="checkResultCodeNEq1" prepend="and">
                        rl.CHECK_RESULT_CODE != #checkResultCodeNEq1#
                </isNotNull>
          </dynamic>
    </select>

dynamic的prepend只要检测到第一个为“真”的条件比较元素(isNotNull标签)，则覆盖其prepend属性并组装where关键字为动态SQL的一部分.