diff --git a/src/main/java/com/lovenav/controller/CommentController.java b/src/main/java/com/lovenav/controller/CommentController.java
index 7a2334c..0f8dbeb 100644
--- a/src/main/java/com/lovenav/controller/CommentController.java
+++ b/src/main/java/com/lovenav/controller/CommentController.java
@@ -71,7 +71,7 @@ public class CommentController {
     }
 
     @RequestMapping("/comment/deleteByCommentId")
-    public String deleteByCommentId(String commentId)
+    public String deleteByCommentId(Integer commentId)
     {
         HashMap<String, Object> result = new HashMap<>();
         result.put("code", 200);
diff --git a/src/main/java/com/lovenav/dao/CommentDao.java b/src/main/java/com/lovenav/dao/CommentDao.java
index fbd4a7c..0e93025 100644
--- a/src/main/java/com/lovenav/dao/CommentDao.java
+++ b/src/main/java/com/lovenav/dao/CommentDao.java
@@ -44,5 +44,5 @@ public interface CommentDao {
 
     List<CommentNode> querySecondCommentList(Integer UrlId);
 
-    public String queryChildId(String commentId);
+    public String queryChildId(Integer commentId);
 }
\ No newline at end of file
diff --git a/src/main/java/com/lovenav/service/CommentService.java b/src/main/java/com/lovenav/service/CommentService.java
index b88521b..bd4758d 100644
--- a/src/main/java/com/lovenav/service/CommentService.java
+++ b/src/main/java/com/lovenav/service/CommentService.java
@@ -27,5 +27,5 @@ public interface CommentService {
 
     CommentUser queryCommentUserById(Integer id);
 
-    public String SelectChildAndDelete(String commentId);
+    public String SelectChildAndDelete(Integer commentId);
 }
diff --git a/src/main/java/com/lovenav/service/serviceImpl/CommentServiceImpl.java b/src/main/java/com/lovenav/service/serviceImpl/CommentServiceImpl.java
index fb4d2dc..1b0eefc 100644
--- a/src/main/java/com/lovenav/service/serviceImpl/CommentServiceImpl.java
+++ b/src/main/java/com/lovenav/service/serviceImpl/CommentServiceImpl.java
@@ -179,7 +179,7 @@ public class CommentServiceImpl implements CommentService {
         }
         return firstList;
     }
-    public String SelectChildAndDelete(String commentId)
+    public String SelectChildAndDelete(Integer commentId)
     {
 
         String child = commentDao.queryChildId(commentId);
diff --git a/src/main/resources/mybatis/CommentDao.xml b/src/main/resources/mybatis/CommentDao.xml
index d59e415..1422e1b 100644
--- a/src/main/resources/mybatis/CommentDao.xml
+++ b/src/main/resources/mybatis/CommentDao.xml
@@ -56,7 +56,7 @@
     where id = #{id,jdbcType=INTEGER}
   </delete>
 
-  <select id="queryChildId" parameterType="java.lang.String" resultType="java.lang.String">
+  <select id="queryChildId" parameterType="java.lang.Integer" resultType="java.lang.String">
     SELECT t3.ischild
     FROM(SELECT t1.*,
                 IF (FIND_IN_SET(root_comment_id, @pids) > 0,@pids := CONCAT(@pids, ',', id),'0') AS ischild
@@ -65,6 +65,8 @@
               ORDER BY t.id ASC) t1,
              (SELECT @pids := #{commentId,jdbcType=INTEGER}) t2) t3
     WHERE ischild != '0'
+    order by id desc
+    limit 1
   </select>