diff --git a/RuoYi-Vue/ruoyi-train/src/main/java/com/ruoyi/train/mapper/TrainAccommodationMapper.java b/RuoYi-Vue/ruoyi-train/src/main/java/com/ruoyi/train/mapper/TrainAccommodationMapper.java
index 7506c37fa..d53566a0a 100644
--- a/RuoYi-Vue/ruoyi-train/src/main/java/com/ruoyi/train/mapper/TrainAccommodationMapper.java
+++ b/RuoYi-Vue/ruoyi-train/src/main/java/com/ruoyi/train/mapper/TrainAccommodationMapper.java
@@ -69,6 +69,18 @@ public interface TrainAccommodationMapper
      */
     public int countActiveByDormId(@Param("dormId") String dormId);
 
+    /**
+     * 统计指定宿舍和床位当前处于有效状态 (0预分配, 1已入住) 的住宿记录数
+     *
+     * @param dormId 宿舍ID
+     * @param bedNo 床位号
+     * @param excludeAccommodationId 排除的自身住宿ID (更新时排除自身)
+     * @return 冲突占用数
+     */
+    public int countActiveByDormIdAndBedNo(@Param("dormId") String dormId,
+                                           @Param("bedNo") String bedNo,
+                                           @Param("excludeAccommodationId") Long excludeAccommodationId);
+
     /**
      * 新增住宿安排
      *
diff --git a/RuoYi-Vue/ruoyi-train/src/main/java/com/ruoyi/train/service/impl/TrainAccommodationServiceImpl.java b/RuoYi-Vue/ruoyi-train/src/main/java/com/ruoyi/train/service/impl/TrainAccommodationServiceImpl.java
index cad9e4dae..6234b2898 100644
--- a/RuoYi-Vue/ruoyi-train/src/main/java/com/ruoyi/train/service/impl/TrainAccommodationServiceImpl.java
+++ b/RuoYi-Vue/ruoyi-train/src/main/java/com/ruoyi/train/service/impl/TrainAccommodationServiceImpl.java
@@ -169,7 +169,17 @@ public class TrainAccommodationServiceImpl implements ITrainAccommodationService
                 + "，当前有效人数: " + currentActive + ")，无法继续分配");
         }
 
-        // 5. 设置默认属性
+        // 5. 验证床位唯一占用约束 (Active Bed Uniqueness Guard: MAJ-06)
+        if (accommodation.getBedNo() != null && !accommodation.getBedNo().trim().isEmpty())
+        {
+            int bedOccupied = trainAccommodationMapper.countActiveByDormIdAndBedNo(dormId, accommodation.getBedNo().trim(), null);
+            if (bedOccupied > 0)
+            {
+                throw new ServiceException("BED_ALREADY_OCCUPIED: 该床位当前已被占用 (宿舍: " + dormId + "，床位: " + accommodation.getBedNo() + ")");
+            }
+        }
+
+        // 6. 设置默认属性
         if (accommodation.getAssignedTime() == null)
         {
             accommodation.setAssignedTime(DateUtils.getNowDate());
@@ -215,6 +225,18 @@ public class TrainAccommodationServiceImpl implements ITrainAccommodationService
             throw new ServiceException("变更宿舍请使用专属调房换房流程 (transfer)，禁止直接修改住宿记录的宿舍ID");
         }
 
+        // 验证床位唯一占用约束 (更新时排除自身)
+        String targetDormId = accommodation.getDormId() != null ? accommodation.getDormId() : exist.getDormId();
+        String targetBedNo = accommodation.getBedNo() != null ? accommodation.getBedNo().trim() : (exist.getBedNo() != null ? exist.getBedNo().trim() : null);
+        if (targetBedNo != null && !targetBedNo.isEmpty())
+        {
+            int bedOccupied = trainAccommodationMapper.countActiveByDormIdAndBedNo(targetDormId, targetBedNo, exist.getAccommodationId());
+            if (bedOccupied > 0)
+            {
+                throw new ServiceException("BED_ALREADY_OCCUPIED: 该床位当前已被占用 (宿舍: " + targetDormId + "，床位: " + targetBedNo + ")");
+            }
+        }
+
         accommodation.setUpdateTime(DateUtils.getNowDate());
         return trainAccommodationMapper.updateTrainAccommodation(accommodation);
     }
diff --git a/RuoYi-Vue/ruoyi-train/src/main/resources/mapper/train/TrainAccommodationMapper.xml b/RuoYi-Vue/ruoyi-train/src/main/resources/mapper/train/TrainAccommodationMapper.xml
index 494b10e6d..c8ca7b33c 100644
--- a/RuoYi-Vue/ruoyi-train/src/main/resources/mapper/train/TrainAccommodationMapper.xml
+++ b/RuoYi-Vue/ruoyi-train/src/main/resources/mapper/train/TrainAccommodationMapper.xml
@@ -129,6 +129,17 @@ PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
           AND accommodation_status IN (0, 1)
     </select>
 
+    <select id="countActiveByDormIdAndBedNo" resultType="int">
+        SELECT COUNT(1)
+        FROM train_accommodation
+        WHERE dorm_id = #{dormId}
+          AND bed_no = #{bedNo}
+          AND accommodation_status IN (0, 1)
+          <if test="excludeAccommodationId != null">
+              AND accommodation_id != #{excludeAccommodationId}
+          </if>
+    </select>
+
     <insert id="insertTrainAccommodation" parameterType="TrainAccommodation" useGeneratedKeys="true" keyProperty="accommodationId">
         INSERT INTO train_accommodation
         <trim prefix="(" suffix=")" suffixOverrides=",">
diff --git a/RuoYi-Vue/ruoyi-train/src/test/java/com/ruoyi/train/service/impl/AccommodationServiceTest.java b/RuoYi-Vue/ruoyi-train/src/test/java/com/ruoyi/train/service/impl/AccommodationServiceTest.java
index d11f6c250..d0661e7e3 100644
--- a/RuoYi-Vue/ruoyi-train/src/test/java/com/ruoyi/train/service/impl/AccommodationServiceTest.java
+++ b/RuoYi-Vue/ruoyi-train/src/test/java/com/ruoyi/train/service/impl/AccommodationServiceTest.java
@@ -609,6 +609,31 @@ public class AccommodationServiceTest
             return count;
         }
 
+        @Override
+        public int countActiveByDormIdAndBedNo(String dormId, String bedNo, Long excludeAccommodationId)
+        {
+            if (dormId == null || bedNo == null || bedNo.trim().isEmpty()) {
+                return 0;
+            }
+            int count = 0;
+            for (TrainAccommodation a : store.values())
+            {
+                if (excludeAccommodationId != null && excludeAccommodationId.equals(a.getAccommodationId()))
+                {
+                    continue;
+                }
+                if (dormId.equals(a.getDormId()) && bedNo.equals(a.getBedNo()))
+                {
+                    if (TrainAccommodation.STATUS_PREALLOCATED.equals(a.getAccommodationStatus())
+                        || TrainAccommodation.STATUS_CHECKED_IN.equals(a.getAccommodationStatus()))
+                    {
+                        count++;
+                    }
+                }
+            }
+            return count;
+        }
+
         @Override
         public int insertTrainAccommodation(TrainAccommodation accommodation)
         {
diff --git a/RuoYi-Vue/sql/system/kingbase/015_dms_package_a_hardening.sql b/RuoYi-Vue/sql/system/kingbase/015_dms_package_a_hardening.sql
new file mode 100644
index 000000000..3695a67d6
--- /dev/null
+++ b/RuoYi-Vue/sql/system/kingbase/015_dms_package_a_hardening.sql
@@ -0,0 +1,119 @@
+-- ============================================================================
+-- Migration: 015_dms_package_a_hardening.sql
+-- Description: Package A.1 DMS 一致性加固与最小权限拆分
+-- 1. 权限最小化拆分：新增 2194 (train:access:credential)，从 train_admin 移除 2192 (train:access:manage)
+-- 2. 床位唯一性约束：检测无重复记录时创建有效床位部分唯一索引
+-- 3. 幂等与断言校验
+-- ============================================================================
+
+\set ON_ERROR_STOP on
+
+BEGIN;
+
+-- 1. 注册 2194 (train:access:credential) 门禁凭据下发与注销专用权限
+INSERT INTO public.sys_menu
+    (menu_id, menu_name, parent_id, order_num, path, component, query, is_frame, is_cache,
+     menu_type, visible, status, perms, icon, create_by, create_time, update_by, update_time, remark)
+SELECT 2194, '门禁凭据操作', 2060, 4, '#', '', '', 1, 0,
+       'F', '0', '0', 'train:access:credential', '#', 'admin', CURRENT_TIMESTAMP, '', NULL, '门禁凭据下发与注销权限'
+WHERE NOT EXISTS (SELECT 1 FROM public.sys_menu WHERE menu_id = 2194);
+
+-- 2. 超级管理员角色 (role_id = 1) 授予 2194
+INSERT INTO public.sys_role_menu (role_id, menu_id)
+SELECT 1, 2194
+WHERE NOT EXISTS (SELECT 1 FROM public.sys_role_menu WHERE role_id = 1 AND menu_id = 2194);
+
+-- 3. 培训管理员角色 (role_id = 3) 调整权限 (MIN-09)：
+-- 授予 2194 (train:access:credential)
+INSERT INTO public.sys_role_menu (role_id, menu_id)
+SELECT 3, 2194
+WHERE NOT EXISTS (SELECT 1 FROM public.sys_role_menu WHERE role_id = 3 AND menu_id = 2194);
+
+-- 从 train_admin (role_id = 3) 回收 2192 (train:access:manage，硬件映射与维护权限)
+DELETE FROM public.sys_role_menu
+WHERE role_id = 3 AND menu_id = 2192;
+
+-- 从 train_admin (role_id = 3) 回收 2263 (train:accommodation:remove，物理删除住宿历史权限)
+DELETE FROM public.sys_role_menu
+WHERE role_id = 3 AND menu_id = 2263;
+
+-- 4. 有效床位唯一性约束 (Section 17)
+-- 先只读检查是否存在已有的活跃床位重复数据
+DO $$
+DECLARE
+    v_dup_groups INTEGER;
+BEGIN
+    SELECT COUNT(*) INTO v_dup_groups FROM (
+        SELECT dorm_id, bed_no
+        FROM train_accommodation
+        WHERE accommodation_status IN (0, 1)
+          AND bed_no IS NOT NULL
+        GROUP BY dorm_id, bed_no
+        HAVING COUNT(*) > 1
+    ) t;
+
+    IF v_dup_groups = 0 THEN
+        IF NOT EXISTS (
+            SELECT 1 FROM pg_class c
+            JOIN pg_namespace n ON n.oid = c.relnamespace
+            WHERE c.relname = 'idx_train_acc_dorm_bed_active_uniq'
+        ) THEN
+            CREATE UNIQUE INDEX idx_train_acc_dorm_bed_active_uniq
+            ON train_accommodation (dorm_id, bed_no)
+            WHERE accommodation_status IN (0, 1) AND bed_no IS NOT NULL;
+            RAISE NOTICE 'Created partial unique index idx_train_acc_dorm_bed_active_uniq successfully.';
+        END IF;
+    ELSE
+        RAISE NOTICE 'ACTIVE_BED_DUPLICATE_GROUP_COUNT = %, skipping unique index creation to prevent business data destruction.', v_dup_groups;
+    END IF;
+END $$;
+
+-- 5. 状态机约束兼容性检查 (train_external_operation)
+-- 确保 operation_status 允许 DISPATCHING 与 AMBIGUOUS
+DO $$
+DECLARE
+    v_conname TEXT;
+BEGIN
+    SELECT conname INTO v_conname
+    FROM pg_constraint
+    WHERE conrelid = 'train_external_operation'::regclass
+      AND contype = 'c'
+      AND pg_get_constraintdef(oid) LIKE '%operation_status%';
+
+    IF v_conname IS NOT NULL THEN
+        EXECUTE 'ALTER TABLE train_external_operation DROP CONSTRAINT ' || quote_ident(v_conname);
+        EXECUTE 'ALTER TABLE train_external_operation ADD CONSTRAINT chk_external_operation_status ' ||
+                'CHECK (operation_status IN (''CREATED'',''DISPATCHING'',''REQUESTED'',''ACCEPTED'',''PENDING'',''RETRY_WAIT'',''AMBIGUOUS'',''SUCCESS'',''FAILED'',''TIMEOUT''))';
+    END IF;
+END $$;
+
+-- 6. 后置断言验证
+DO $$
+BEGIN
+    -- 断言 1: 2194 已正确注册
+    IF (SELECT count(*) FROM public.sys_menu WHERE menu_id = 2194 AND perms = 'train:access:credential' AND status = '0') <> 1 THEN
+        RAISE EXCEPTION 'Assertion failed: menu 2194 train:access:credential not found or invalid';
+    END IF;
+
+    -- 断言 2: train_admin (role_id = 3) 拥有 2194 (train:access:credential)
+    IF (SELECT count(*) FROM public.sys_role_menu WHERE role_id = 3 AND menu_id = 2194) <> 1 THEN
+        RAISE EXCEPTION 'Assertion failed: role 3 not granted menu 2194';
+    END IF;
+
+    -- 断言 3: train_admin (role_id = 3) 不得拥有 2192 (train:access:manage)
+    IF (SELECT count(*) FROM public.sys_role_menu WHERE role_id = 3 AND menu_id = 2192) <> 0 THEN
+        RAISE EXCEPTION 'Assertion failed: role 3 still has menu 2192 (train:access:manage)';
+    END IF;
+
+    -- 断言 4: train_admin (role_id = 3) 不得拥有 2263 (train:accommodation:remove)
+    IF (SELECT count(*) FROM public.sys_role_menu WHERE role_id = 3 AND menu_id = 2263) <> 0 THEN
+        RAISE EXCEPTION 'Assertion failed: role 3 has forbidden menu 2263 (train:accommodation:remove)';
+    END IF;
+
+    -- 断言 5: train_admin 拥有 2264 (train:accommodation:add)
+    IF (SELECT count(*) FROM public.sys_role_menu WHERE role_id = 3 AND menu_id = 2264) <> 1 THEN
+        RAISE EXCEPTION 'Assertion failed: role 3 missing menu 2264 (train:accommodation:add)';
+    END IF;
+END $$;
+
+COMMIT;