mybatis中的动态语句中多条件or如何书写

1.说明

  sql如下:

SELECT t.contract_id FROM `t_plm_contract_monitor` t WHERE 1=1 ANd (t.whole_id_one in ( 77 ) or t.whole_id_five in ( 77 ) or t.whole_id_six in ( 505602294 ))

  说明:

t.whole_id_one,
t.whole_id_two,
t.whole_id_three,
t.whole_id_four,
t.whole_id_five,
t.whole_id_six

这些参数可能存在,也可能不存在,就要动态的平装语句了。

2.做法【部分代码进行说明】

          <if test="(model.wholeIdOneList != null and model.wholeIdOneList.size()> 0) or (model.wholeIdTwoList != null and model.wholeIdTwoList.size()> 0) or
                   (model.wholeIdThreeList != null and model.wholeIdThreeList.size()> 0) or (model.wholeIdFourList != null and model.wholeIdFourList.size()> 0) or
                   (model.wholeIdFiveList != null and model.wholeIdFiveList.size()> 0) or (model.wholeIdSixList != null and model.wholeIdSixList.size()> 0)">
                    and (
                </if>
                <if test="model.wholeIdOneList != null and model.wholeIdOneList.size()> 0">
                    t.whole_id_one in
                    <foreach collection="model.wholeIdOneList" open="(" close=")" item="departmentId" separator=",">
                        #{departmentId,jdbcType=BIGINT}
                    </foreach>
                </if>
                <choose>
                    <when test="(model.wholeIdOneList == null or model.wholeIdOneList.size()==0) and (model.wholeIdTwoList != null and model.wholeIdTwoList.size()> 0)">
                        t.whole_id_two in
                        <foreach collection="model.wholeIdTwoList" open="(" close=")" item="departmentId" separator=",">
                            #{departmentId,jdbcType=BIGINT}
                        </foreach>
                    </when>
                    <when test="(model.wholeIdOneList != null and model.wholeIdOneList.size()> 0) and (model.wholeIdTwoList != null and model.wholeIdTwoList.size()> 0)">
                        OR t.whole_id_two in
                        <foreach collection="model.wholeIdTwoList" open="(" close=")" item="departmentId" separator=",">
                            #{departmentId,jdbcType=BIGINT}
                        </foreach>
                    </when>
                </choose>

。。。。。。。

  首先:根据值是否存在,将是否有这段逻辑的最外层的括号加进来

       然后,使用test进行判断list,如果前面的都不存在条件,第n个存在,则不需要加上or连接符

                  如果已经不是第一项了,则需要加上or。

3.对choose的说明

  在比较规范的标签里,存在when和otherwise。

       但是有些场景下是不需要的,则可以不写otherwise。经过验证是没有问题的。



原文地址:https://www.cnblogs.com/juncaoit/p/12342555.html