修复：产品管理搜索

src/main/resources/mapper/ProductDao.xml

@@ -108,7 +108,7 @@
                 and product_name like CONCAT ('%',#{productName},'%')
             </if>
             <if test="type != null">
-                and `type` = #{type}
+                and (`type` = #{type} or `type` is null)
             </if>
         </where>
     </select>
@@ -131,7 +131,7 @@
                 and ps.product_name like CONCAT ('%',#{productName},'%')
             </if>
             <if test="type != null">
-                and `type` = #{type} or `type` is null
+                and (`type` = #{type} or `type` is null)
             </if>
         </where>
         order by ps.create_time desc