diff --git a/smoke/smoke.mjs b/smoke/smoke.mjs
index 2032c3c..b84c0dc 100644
--- a/smoke/smoke.mjs
+++ b/smoke/smoke.mjs
@@ -98,6 +98,9 @@ ok("classroom Edit equipments 按数量替换", editQty.code === 0, editQty.msg)
 const roomsAfterQty = await api("GET", "/api/classroom/List", { params: { buildingId, page: 1, count: 20 } });
 const room1Qty = roomsAfterQty.data.list.find(r => r.serID === room1);
 ok("Edit 后设备数量为 3（名称×3）", room1Qty && room1Qty.equipmentQtys && room1Qty.equipmentQtys[eqSeedId] === 3 && /冒烟设备.*×3$/.test(room1Qty.equipmentNames), JSON.stringify(room1Qty && room1Qty.equipmentQtys));
+// 回归：编辑时保留原有设备关联（先删后插撞 (classroom_id, equipment_id) 唯一键）
+const editKeep = await api("POST", "/api/classroom/Edit", { json: { serID: room1, status: "closed", equipments: [{ equipmentId: eqSeedId, quantity: 3 }] } });
+ok("classroom Edit 保留原设备关联", editKeep.code === 0, editKeep.msg);
 const editClear = await api("POST", "/api/classroom/Edit", { json: { serID: room1, equipmentIds: [] } });
 ok("classroom Edit 旧字段 equipmentIds 清空设备（兼容）", editClear.code === 0, editClear.msg);
 const room2code = roomsAfterEdit.data.list[1].roomCode;
diff --git a/src/main/java/com/yunhai/acaclassroom/controller/api/ClassroomController.java b/src/main/java/com/yunhai/acaclassroom/controller/api/ClassroomController.java
index 7dbb0f6..bba5109 100644
--- a/src/main/java/com/yunhai/acaclassroom/controller/api/ClassroomController.java
+++ b/src/main/java/com/yunhai/acaclassroom/controller/api/ClassroomController.java
@@ -50,7 +50,7 @@ public class ClassroomController {
         return classroomService.floors(buildingId);
     }
 
-    /** 全校教室扁平列表（教室管理页「空间筛选树」数据源，轻量字段）。 */
+    /** 全校教室扁平列表（教室管理页「楼层筛选树」数据源，轻量字段）。 */
     @GetMapping("Tree")
     public List<Map<String, Object>> tree() {
         return classroomService.tree();
diff --git a/src/main/java/com/yunhai/acaclassroom/service/IClassroomService.java b/src/main/java/com/yunhai/acaclassroom/service/IClassroomService.java
index bcd56a7..ac8e492 100644
--- a/src/main/java/com/yunhai/acaclassroom/service/IClassroomService.java
+++ b/src/main/java/com/yunhai/acaclassroom/service/IClassroomService.java
@@ -36,7 +36,7 @@ public interface IClassroomService {
     /** 楼栋下已有教室的楼层列表（升序，筛选项用）。 */
     List<Integer> floors(Integer buildingId);
 
-    /** 全校教室扁平列表（空间筛选树数据源，仅轻量字段）。 */
+    /** 全校教室扁平列表（楼层筛选树数据源，仅轻量字段）。 */
     List<Map<String, Object>> tree();
 
     /** 批量添加教室，返回 {created, skipped, total}。 */
diff --git a/src/main/java/com/yunhai/acaclassroom/service/impl/ClassroomService.java b/src/main/java/com/yunhai/acaclassroom/service/impl/ClassroomService.java
index aaf8943..8492d15 100644
--- a/src/main/java/com/yunhai/acaclassroom/service/impl/ClassroomService.java
+++ b/src/main/java/com/yunhai/acaclassroom/service/impl/ClassroomService.java
@@ -128,7 +128,7 @@ public class ClassroomService implements IClassroomService {
         // 类型名映射
         Map<Integer, String> typeNames = typeRepository.findBySchIdOrderBySortOrderAscIdAsc(schId).stream()
                 .collect(Collectors.toMap(ClassroomType::getId, ClassroomType::getTypeName, (a, b) -> a));
-        // 校区/楼栋名映射（列表跨楼栋时行内直接展示，空间筛选树与详情面板用）
+        // 校区/楼栋名映射（列表跨楼栋时行内直接展示，楼层筛选树与详情面板用）
         Map<Integer, String> campusNames = campusRepository.findBySchIdOrderBySortOrderAscIdAsc(schId).stream()
                 .collect(Collectors.toMap(com.yunhai.acaclassroom.entity.Campus::getId,
                         com.yunhai.acaclassroom.entity.Campus::getCampusName, (a, b) -> a));
@@ -357,6 +357,9 @@ public class ClassroomService implements IClassroomService {
             Map<Integer, Integer> equipmentMap =
                     sanitizeEquipmentMap(req.getEquipments(), req.getEquipmentIds(), r.getSchId());
             classroomEquipmentRepository.deleteBySchIdAndClassroomId(r.getSchId(), r.getId());
+            // 先落盘删除：Hibernate 同一事务内 INSERT 先于 DELETE 执行，
+            // 不 flush 会让“保留原设备”的重插撞 (classroom_id, equipment_id) 唯一键。
+            classroomEquipmentRepository.flush();
             equipmentMap.forEach((eqId, qty) -> {
                 com.yunhai.acaclassroom.entity.ClassroomEquipment ce =
                         new com.yunhai.acaclassroom.entity.ClassroomEquipment();