mybatis–foreach loop update modification
When judging, double primary key or multiple judgments need to judge when multiple fields and where in multiple fields
<update id="updateAppSetDatas" parameterType="list">
update app_set_data
<set>
<trim prefix="appName=case" suffix="end,">
<foreach collection="appSetDatas" item="item" index="index">
<if test="item.app_name != null and item.app_name != ''">
when area_id=#{
item.areaId} and app_id =#{
item.appId} then #{
item.app_name}
</if>
<if test="item.app_name == null and item.app_name == ''">
when area_id=#{
item.areaId} and app_id =#{
item.appId} then app_set_data.appName
</if>
</foreach>
</trim>
<trim prefix="pass_reader1=case" suffix="end,">
<foreach collection="appSetDatas" item="item" index="index">
<if test="item.passReader1 != null">
when area_id=#{
item.areaId} and app_id =#{
item.appId} then #{
item.passReader1}
</if>
<if test="item.passReader1 == null">
when area_id=#{
item.areaId} and app_id =#{
item.appId} then app_set_data.pass_reader1
</if>
</foreach>
</trim>
<trim prefix="update_time=case" suffix="end,">
<foreach collection="appSetDatas" item="item" index="index">
<if test="item.updateTime != null">
when area_id=#{
item.areaId} and app_id =#{
item.appId} then #{
item.updateTime}
</if>
<if test="item.updateTime == null">
when area_id=#{
item.areaId} and app_id =#{
item.appId} then app_set_data.update_time
</if>
</foreach>
</trim>
</set>
where (area_id,app_id) in
<foreach collection="appSetDatas" item="item" index="index" separator="," open="(" close=")">
(#{
item.areaId},#{
item.appId})
</foreach>
</update>