diff --git a/backend/src/main/java/com/xly/erp/module/usr/mapper/PermissionCategoryMapper.java b/backend/src/main/java/com/xly/erp/module/usr/mapper/PermissionCategoryMapper.java
new file mode 100644
index 0000000..171b13c
--- /dev/null
+++ b/backend/src/main/java/com/xly/erp/module/usr/mapper/PermissionCategoryMapper.java
@@ -0,0 +1,18 @@
+package com.xly.erp.module.usr.mapper;
+
+import org.apache.ibatis.annotations.Mapper;
+import org.apache.ibatis.annotations.Param;
+import org.apache.ibatis.annotations.Select;
+
+import java.util.List;
+
+@Mapper
+public interface PermissionCategoryMapper {
+
+    @Select("<script>"
+            + "SELECT COUNT(1) FROM tPermissionCategory "
+            + "WHERE bDeleted = 0 AND iIncrement IN "
+            + "<foreach collection='ids' item='id' open='(' separator=',' close=')'>#{id}</foreach>"
+            + "</script>")
+    int countActiveByIds(@Param("ids") List<Integer> ids);
+}
diff --git a/backend/src/main/java/com/xly/erp/module/usr/mapper/StaffMapper.java b/backend/src/main/java/com/xly/erp/module/usr/mapper/StaffMapper.java
new file mode 100644
index 0000000..e06946f
--- /dev/null
+++ b/backend/src/main/java/com/xly/erp/module/usr/mapper/StaffMapper.java
@@ -0,0 +1,16 @@
+package com.xly.erp.module.usr.mapper;
+
+import org.apache.ibatis.annotations.Mapper;
+import org.apache.ibatis.annotations.Param;
+import org.apache.ibatis.annotations.Select;
+
+@Mapper
+public interface StaffMapper {
+
+    @Select("SELECT 1 FROM tStaff WHERE iIncrement = #{id} AND bDeleted = 0 LIMIT 1")
+    Integer findActiveStaffFlag(@Param("id") Integer id);
+
+    default boolean existsActiveById(Integer id) {
+        return findActiveStaffFlag(id) != null;
+    }
+}
diff --git a/backend/src/test/java/com/xly/erp/module/usr/mapper/PermissionCategoryMapperIT.java b/backend/src/test/java/com/xly/erp/module/usr/mapper/PermissionCategoryMapperIT.java
new file mode 100644
index 0000000..104d053
--- /dev/null
+++ b/backend/src/test/java/com/xly/erp/module/usr/mapper/PermissionCategoryMapperIT.java
@@ -0,0 +1,51 @@
+package com.xly.erp.module.usr.mapper;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.test.context.ActiveProfiles;
+
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.NONE)
+@ActiveProfiles("test")
+class PermissionCategoryMapperIT {
+
+    @Autowired
+    private PermissionCategoryMapper permissionCategoryMapper;
+
+    @Autowired
+    private JdbcTemplate jdbcTemplate;
+
+    @BeforeEach
+    @AfterEach
+    void cleanup() {
+        jdbcTemplate.update("DELETE FROM tPermissionCategory WHERE sCategoryCode LIKE 'sp_test_%'");
+    }
+
+    @Test
+    void countActiveByIds_returnsCorrectCount() {
+        Integer cat1 = insertCategory("sp_test_c1", "权限1", false);
+        Integer cat2 = insertCategory("sp_test_c2", "权限2", false);
+        Integer cat3 = insertCategory("sp_test_c3", "权限3", true);
+
+        assertThat(permissionCategoryMapper.countActiveByIds(List.of(cat1, cat2, cat3))).isEqualTo(2);
+        assertThat(permissionCategoryMapper.countActiveByIds(List.of(cat1, 99999991))).isEqualTo(1);
+        assertThat(permissionCategoryMapper.countActiveByIds(List.of(99999991))).isZero();
+    }
+
+    private Integer insertCategory(String code, String name, boolean deleted) {
+        jdbcTemplate.update(
+                "INSERT INTO tPermissionCategory (sBrandsId, sSubsidiaryId, tCreateDate, sCategoryCode, sCategoryName, "
+                        + "iSortOrder, sCreatedBy, bDeleted) "
+                        + "VALUES ('XLY','XLY', NOW(), ?, ?, 0, 'STUB_ADMIN', ?)",
+                code, name, deleted ? 1 : 0);
+        return jdbcTemplate.queryForObject(
+                "SELECT iIncrement FROM tPermissionCategory WHERE sCategoryCode = ?", Integer.class, code);
+    }
+}
diff --git a/backend/src/test/java/com/xly/erp/module/usr/mapper/StaffMapperIT.java b/backend/src/test/java/com/xly/erp/module/usr/mapper/StaffMapperIT.java
new file mode 100644
index 0000000..52c74c4
--- /dev/null
+++ b/backend/src/test/java/com/xly/erp/module/usr/mapper/StaffMapperIT.java
@@ -0,0 +1,47 @@
+package com.xly.erp.module.usr.mapper;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.test.context.ActiveProfiles;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.NONE)
+@ActiveProfiles("test")
+class StaffMapperIT {
+
+    @Autowired
+    private StaffMapper staffMapper;
+
+    @Autowired
+    private JdbcTemplate jdbcTemplate;
+
+    @BeforeEach
+    @AfterEach
+    void cleanup() {
+        jdbcTemplate.update("DELETE FROM tStaff WHERE sStaffNo LIKE 'sp_test_%'");
+    }
+
+    @Test
+    void existsActiveById_handlesAliveDeletedMissing() {
+        Integer aliveId = insertStaff("sp_test_st_alive", "活的", false);
+        Integer deletedId = insertStaff("sp_test_st_dead", "死的", true);
+
+        assertThat(staffMapper.existsActiveById(aliveId)).isTrue();
+        assertThat(staffMapper.existsActiveById(deletedId)).isFalse();
+        assertThat(staffMapper.existsActiveById(99999990)).isFalse();
+    }
+
+    private Integer insertStaff(String staffNo, String staffName, boolean deleted) {
+        jdbcTemplate.update(
+                "INSERT INTO tStaff (sBrandsId, sSubsidiaryId, tCreateDate, sStaffNo, sStaffName, sCreatedBy, bDeleted) "
+                        + "VALUES ('XLY','XLY', NOW(), ?, ?, 'STUB_ADMIN', ?)",
+                staffNo, staffName, deleted ? 1 : 0);
+        return jdbcTemplate.queryForObject(
+                "SELECT iIncrement FROM tStaff WHERE sStaffNo = ?", Integer.class, staffNo);
+    }
+}