diff --git a/src/main/resources/mapper/PostMapper.xml b/src/main/resources/mapper/PostMapper.xml
index e676fcc..ad6024c 100644
--- a/src/main/resources/mapper/PostMapper.xml
+++ b/src/main/resources/mapper/PostMapper.xml
@@ -78,7 +78,7 @@
     <!-- 更新置顶状态 -->
     <update id="updatePinnedStatus" parameterType="map">
         UPDATE post
-        SET is_pinned = #{pinned}
+        SET is_pinned = #{isPinned}
         WHERE postid = #{postid}
     </update>
 
@@ -100,4 +100,10 @@
         ORDER BY is_pinned DESC, postCreatedTime DESC
     </select>
 
+    <!-- ✅ 根据 postid 查询单个帖子 -->
+    <select id="selectById" parameterType="int" resultType="com.pt5.pthouduan.entity.Post">
+        SELECT * FROM post
+        WHERE postid = #{postid}
+    </select>
+
 </mapper>