diff --git a/server/imserver/dbengine.cc b/server/imserver/dbengine.cc
index d280162..edbb3f7 100644
--- a/server/imserver/dbengine.cc
+++ b/server/imserver/dbengine.cc
@@ -83,7 +83,8 @@ a8::XObject DBEngine::GetConnInfo(const std::string& data)
 
 a8::XObject DBEngine::GetConnInfo(long long data)
 {
-    std::shared_ptr<a8::XObject> mysql_cluster_conf = JsonDataMgr::Instance()->GetMysqlClusterConf();
+    std::shared_ptr<a8::XObject> mysql_cluster_conf =
+        JsonDataMgr::Instance()->GetMysqlClusterConf();
     if (mysql_cluster_conf->Size() <= 0) {
         abort();
     }
@@ -93,22 +94,49 @@ a8::XObject DBEngine::GetConnInfo(long long data)
 
 void DBEngine::UpdateFriendApplyIdx(long long crc32_code, long long new_idx)
 {
-    friend_apply_idx_hash_[crc32_code] = new_idx;
+    if (GetFriendApplyCurrIdx(crc32_code) < new_idx) {
+        friend_apply_idx_hash_[GetInstanceId(crc32_code)] = new_idx;
+    }
 }
 
 long long DBEngine::GetFriendApplyCurrIdx(long long crc32_code)
 {
-    auto itr = friend_apply_idx_hash_.find(crc32_code);
+    auto itr = friend_apply_idx_hash_.find(GetInstanceId(crc32_code));
     return itr != friend_apply_idx_hash_.end() ? itr->second : 0;
 }
 
 void DBEngine::UpdateGroupApplyIdx(long long crc32_code, long long new_idx)
 {
-    group_apply_idx_hash_[crc32_code] = new_idx;
+    if (GetGroupApplyCurrIdx(crc32_code) < new_idx) {
+        group_apply_idx_hash_[GetInstanceId(crc32_code)] = new_idx;
+    }
 }
 
 long long DBEngine::GetGroupApplyCurrIdx(long long crc32_code)
 {
-    auto itr = group_apply_idx_hash_.find(crc32_code);
+    auto itr = group_apply_idx_hash_.find(GetInstanceId(crc32_code));
     return itr != group_apply_idx_hash_.end() ? itr->second : 0;
 }
+
+long long DBEngine::GetEventCurrIdx(long long crc32_code)
+{
+    auto itr = event_idx_hash_.find(GetInstanceId(crc32_code));
+    return itr != event_idx_hash_.end() ? itr->second : 0;
+}
+
+void DBEngine::UpdateEventIdx(long long crc32_code, long long new_idx)
+{
+    if (GetEventCurrIdx(crc32_code) < new_idx) {
+        event_idx_hash_[crc32_code] = new_idx;
+    }
+}
+
+int DBEngine::GetInstanceId(long long crc32_code)
+{
+    std::shared_ptr<a8::XObject> mysql_cluster_conf =
+        JsonDataMgr::Instance()->GetMysqlClusterConf();
+    if (mysql_cluster_conf->Size() <= 0) {
+        abort();
+    }
+    return crc32_code % mysql_cluster_conf->Size();
+}
diff --git a/server/imserver/dbengine.h b/server/imserver/dbengine.h
index 677c899..2a96e52 100644
--- a/server/imserver/dbengine.h
+++ b/server/imserver/dbengine.h
@@ -34,13 +34,19 @@ class DBEngine : public a8::Singleton<DBEngine>
 
     long long GetFriendApplyCurrIdx(long long crc32_code);
     long long GetGroupApplyCurrIdx(long long crc32_code);
+    long long GetEventCurrIdx(long long crc32_code);
 
 private:
     void UpdateFriendApplyIdx(long long crc32_code, long long new_idx);
     void UpdateGroupApplyIdx(long long crc32_code, long long new_idx);
+    void UpdateEventIdx(long long crc32_code, long long new_idx);
+
+private:
+    int GetInstanceId(long long crc32_code);
 
 private:
     std::map<long long, long long> friend_apply_idx_hash_;
     std::map<long long, long long> group_apply_idx_hash_;
+    std::map<long long, long long> event_idx_hash_;
 
 };