bug city

src/main/resources/mapper/TaBuildingDynamicMapper.xml

         <if test="buildingId != null and buildingId !=''">
             and building_id = #{buildingId}
         </if>
-        <if test="cityId != 0">
+        <if test="cityId != 0 and cityId != null">
             and city_id = #{cityId}
         </if>
         ORDER BY create_date DESC