diff --git a/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/dal/mysql/device/IotDeviceMapper.java b/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/dal/mysql/device/IotDeviceMapper.java
index 32477221ac..7cc7d5de81 100644
--- a/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/dal/mysql/device/IotDeviceMapper.java
+++ b/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/dal/mysql/device/IotDeviceMapper.java
@@ -6,6 +6,7 @@ import cn.iocoder.yudao.framework.mybatis.core.mapper.BaseMapperX;
 import cn.iocoder.yudao.framework.mybatis.core.query.LambdaQueryWrapperX;
 import cn.iocoder.yudao.module.iot.controller.admin.device.vo.device.IotDevicePageReqVO;
 import cn.iocoder.yudao.module.iot.dal.dataobject.device.IotDeviceDO;
+import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
 import jakarta.annotation.Nullable;
 import org.apache.ibatis.annotations.Mapper;
 
@@ -13,6 +14,7 @@ import java.time.LocalDateTime;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
+import java.util.stream.Collectors;
 
 /**
  * IoT 设备 Mapper
@@ -80,19 +82,33 @@ public interface IotDeviceMapper extends BaseMapperX<IotDeviceDO> {
     }
 
     /**
-     * 查询指定产品下各状态的设备数量
+     * 查询指定产品下的设备数量
      *
-     * @return 设备数量统计列表
+     * @return 产品编号 -> 设备数量的映射
      */
-    // TODO @super：通过 mybatis-plus 来写哈，然后返回 Map  貌似就行了？！
-    List<Map<String, Object>> selectDeviceCountMapByProductId();
+    default Map<Long, Integer> selectDeviceCountMapByProductId() {
+        List<Map<String, Object>> result = selectMaps(new QueryWrapper<IotDeviceDO>()
+                .select("product_id AS productId", "COUNT(1) AS deviceCount")
+                .groupBy("product_id"));
+        return result.stream().collect(Collectors.toMap(
+            map -> Long.valueOf(map.get("productId").toString()),
+            map -> Integer.valueOf(map.get("deviceCount").toString())
+        ));
+    }
 
-    // TODO @super：通过 mybatis-plus 来写哈，然后返回 Map  貌似就行了？！
     /**
      * 查询各个状态下的设备数量
      *
-     * @return 设备数量统计列表
+     * @return 设备状态 -> 设备数量的映射
      */
-    List<Map<String, Object>> selectDeviceCountGroupByState();
+    default Map<Integer, Long> selectDeviceCountGroupByState() {
+        List<Map<String, Object>> result = selectMaps(new QueryWrapper<IotDeviceDO>()
+                .select("state", "COUNT(1) AS deviceCount")
+                .groupBy("state"));
+        return result.stream().collect(Collectors.toMap(
+            map -> Integer.valueOf(map.get("state").toString()),
+            map -> Long.valueOf(map.get("deviceCount").toString())
+        ));
+    }
 
 }
diff --git a/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/service/device/IotDeviceServiceImpl.java b/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/service/device/IotDeviceServiceImpl.java
index 4bb090db41..ccbd652d6e 100644
--- a/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/service/device/IotDeviceServiceImpl.java
+++ b/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/service/device/IotDeviceServiceImpl.java
@@ -36,7 +36,6 @@ import org.springframework.validation.annotation.Validated;
 import javax.annotation.Nullable;
 import java.time.LocalDateTime;
 import java.util.*;
-import java.util.stream.Collectors;
 
 import static cn.iocoder.yudao.framework.common.exception.util.ServiceExceptionUtil.exception;
 import static cn.iocoder.yudao.framework.common.util.collection.CollectionUtils.convertList;
@@ -430,25 +429,14 @@ public class IotDeviceServiceImpl implements IotDeviceService {
         return deviceMapper.selectCountByCreateTime(createTime);
     }
 
-    // TODO @super：简化
     @Override
     public Map<Long, Integer> getDeviceCountMapByProductId() {
-        // 查询结果转换成Map
-        List<Map<String, Object>> list = deviceMapper.selectDeviceCountMapByProductId();
-        return list.stream().collect(Collectors.toMap(
-            map -> Long.valueOf(map.get("key").toString()),
-            map -> Integer.valueOf(map.get("value").toString())
-        ));
+        return deviceMapper.selectDeviceCountMapByProductId();
     }
 
     @Override
     public Map<Integer, Long> getDeviceCountMapByState() {
-        // 查询结果转换成Map
-        List<Map<String, Object>> list = deviceMapper.selectDeviceCountGroupByState();
-        return list.stream().collect(Collectors.toMap(
-            map -> Integer.valueOf(map.get("key").toString()),
-            map -> Long.valueOf(map.get("value").toString())
-        ));
+        return deviceMapper.selectDeviceCountGroupByState();
     }
 
     @Override
diff --git a/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/service/product/IotProductCategoryServiceImpl.java b/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/service/product/IotProductCategoryServiceImpl.java
index 9eb401c634..3c64caedb7 100644
--- a/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/service/product/IotProductCategoryServiceImpl.java
+++ b/yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/service/product/IotProductCategoryServiceImpl.java
@@ -17,6 +17,8 @@ import java.time.LocalDateTime;
 import java.util.*;
 
 import static cn.iocoder.yudao.framework.common.exception.util.ServiceExceptionUtil.exception;
+import static cn.iocoder.yudao.framework.common.util.collection.CollectionUtils.filterList;
+import static cn.iocoder.yudao.framework.common.util.collection.CollectionUtils.getSumValue;
 import static cn.iocoder.yudao.module.iot.enums.ErrorCodeConstants.PRODUCT_CATEGORY_NOT_EXISTS;
 
 /**
@@ -99,23 +101,21 @@ public class IotProductCategoryServiceImpl implements IotProductCategoryService
     @Override
     public Map<String, Integer> getProductCategoryDeviceCountMap() {
         // 1. 获取所有数据
-        List<IotProductCategoryDO> categoryList = iotProductCategoryMapper.selectList();
-        List<IotProductDO> productList = productService.getProductList();
-        // TODO @super：不要 list 查询，返回内存，而是查询一个 Map<productId, count>
+        List<IotProductCategoryDO> categories = iotProductCategoryMapper.selectList();
+        List<IotProductDO> products = productService.getProductList();
         Map<Long, Integer> deviceCountMapByProductId = deviceService.getDeviceCountMapByProductId();
 
         // 2. 统计每个分类下的设备数量
         Map<String, Integer> categoryDeviceCountMap = new HashMap<>();
-        for (IotProductCategoryDO category : categoryList) {
-            categoryDeviceCountMap.put(category.getName(), 0);
-            // TODO @super：CollectionUtils.getSumValue()，看看能不能简化下
-            // 2.2 找到该分类下的所有产品,累加设备数量
-            for (IotProductDO product : productList) {
-                if (Objects.equals(product.getCategoryId(), category.getId())) {
-                    Integer deviceCount = deviceCountMapByProductId.getOrDefault(product.getId(), 0);
-                    categoryDeviceCountMap.merge(category.getName(), deviceCount, Integer::sum);
-                }
-            }
+        for (IotProductCategoryDO category : categories) {
+            // 2.1 找到该分类下的所有产品
+            List<IotProductDO> categoryProducts = filterList(products, 
+                product -> Objects.equals(product.getCategoryId(), category.getId()));
+            // 2.2 累加设备数量
+            Integer totalDeviceCount = getSumValue(categoryProducts, 
+                product -> deviceCountMapByProductId.getOrDefault(product.getId(), 0), 
+                Integer::sum, 0);
+            categoryDeviceCountMap.put(category.getName(), totalDeviceCount);
         }
         return categoryDeviceCountMap;
     }
diff --git a/yudao-module-iot/yudao-module-iot-biz/src/main/resources/mapper/device/IotDeviceMapper.xml b/yudao-module-iot/yudao-module-iot-biz/src/main/resources/mapper/device/IotDeviceMapper.xml
deleted file mode 100644
index 8404729cce..0000000000
--- a/yudao-module-iot/yudao-module-iot-biz/src/main/resources/mapper/device/IotDeviceMapper.xml
+++ /dev/null
@@ -1,25 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE mapper
-        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
-        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
-<mapper namespace="cn.iocoder.yudao.module.iot.dal.mysql.device.IotDeviceMapper">
-
-    <select id="selectDeviceCountGroupByState" resultType="java.util.Map">
-        SELECT 
-            state AS `key`,
-            COUNT(1) AS `value`
-        FROM iot_device
-        WHERE deleted = 0
-        GROUP BY state
-    </select>
-
-    <select id="selectDeviceCountMapByProductId" resultType="java.util.Map">
-        SELECT
-            product_id AS `key`,
-            COUNT(1) AS `value`
-        FROM iot_device
-        WHERE deleted = 0
-        GROUP BY product_id
-    </select>
-
-</mapper>
\ No newline at end of file