diff --git a/broker/src/main/java/io/moquette/persistence/DatabaseStore.java b/broker/src/main/java/io/moquette/persistence/DatabaseStore.java
index a4f12341..e8bcc761 100644
--- a/broker/src/main/java/io/moquette/persistence/DatabaseStore.java
+++ b/broker/src/main/java/io/moquette/persistence/DatabaseStore.java
@@ -1136,7 +1136,6 @@ public class DatabaseStore {
                 "`_type` = ?," +
                 "`_extra` = ?," +
                 "`_dt` = ?," +
-                "`_member_count` = ?," +
                 "`_mute` = ?" +
                 ", `_join_type` = ?" +
                 ", `_private_chat` = ?" +
@@ -1167,7 +1166,6 @@ public class DatabaseStore {
             statement.setInt(index++, groupInfo.getType());
             statement.setString(index++, groupInfo.getExtra());
             statement.setLong(index++, groupInfo.getUpdateDt() == 0 ? System.currentTimeMillis() : groupInfo.getUpdateDt());
-            statement.setInt(index++, groupInfo.getMemberCount());
             statement.setInt(index++, groupInfo.getMute());
             statement.setInt(index++, groupInfo.getJoinType());
             statement.setInt(index++, groupInfo.getPrivateChat());
@@ -1605,12 +1603,10 @@ public class DatabaseStore {
         ResultSet rs = null;
         try {
             connection = DBUtil.getConnection();
-            String sql = "select `_gid` from t_group_member where `_mid` = ? and `_type` <> ?";
+            String sql = "select `_gid` from t_group_member where `_mid` = ? and `_type` <> 4";
             statement = connection.prepareStatement(sql);
 
             statement.setString(1, userId);
-            statement.setInt(2, ProtoConstants.GroupMemberType.GroupMemberType_Removed);
-
 
             rs = statement.executeQuery();
             Set<String> out = new HashSet<>();
@@ -1628,25 +1624,17 @@ public class DatabaseStore {
         }
         return null;
     }
-    void updateGroupMemberCountDt(final String groupId, final int count, final long dt) {
+
+    void updateGroupMemberDt(final String groupId, final long dt) {
         Connection connection = null;
         PreparedStatement statement = null;
         try {
             connection = DBUtil.getConnection();
 
-            String sql ;
-
-            if (count >= 0) {
-                sql = "update t_group set `_member_count` = ?, `_member_dt` = ? , `_dt` = ? where `_gid` = ?";
-            } else {
-                sql = "update t_group set `_member_dt` = ?, `_dt` = ? where `_gid` = ?";
-            }
+            String sql = "update t_group set `_member_dt` = ?, `_dt` = ? where `_gid` = ?";
             statement = connection.prepareStatement(sql);
 
             int index = 1;
-            if (count >=0) {
-                statement.setInt(index++, count);
-            }
             statement.setLong(index++, dt);
             statement.setLong(index++, dt);
             statement.setString(index++, groupId);
@@ -1662,6 +1650,29 @@ public class DatabaseStore {
         }
     }
 
+    void updateGroupMemberCountDt(final String groupId) {
+        Connection connection = null;
+        PreparedStatement statement = null;
+        try {
+            connection = DBUtil.getConnection();
+
+            String sql = "update t_group set `_member_count` = (select count(*) from t_group_member where `_gid` = ? and `_type` <> 4 limit 1), `_dt` = ?, `_member_dt` = `_member_dt` + 1 where `_gid` = ?";
+            statement = connection.prepareStatement(sql);
+            statement.setString(1, groupId);
+            statement.setLong(2, System.currentTimeMillis());
+            statement.setString(3, groupId);
+
+            int c = statement.executeUpdate();
+            LOG.info("Update rows {}", c);
+        } catch (SQLException e) {
+            // TODO Auto-generated catch block
+            e.printStackTrace();
+            Utility.printExecption(LOG, e, RDBS_Exception);
+        } finally {
+            DBUtil.closeDB(connection, statement);
+        }
+    }
+
     void persistGroupMember(final String groupId, final List<WFCMessage.GroupMember> memberList) {
             Connection connection = null;
             PreparedStatement statement = null;
@@ -1724,11 +1735,8 @@ public class DatabaseStore {
     int removeGroupMember(String groupId, List<String> groupMembers) {
         Connection connection = null;
         PreparedStatement statement = null;
-        PreparedStatement statement2 = null;
         try {
             connection = DBUtil.getConnection();
-            connection.setAutoCommit(false);
-
             StringBuilder sqlBuilder = new StringBuilder("update t_group_member set `_type` = ?, `_dt` = ? where `_mid` in (");
             for (int i = 0; i < groupMembers.size(); i++) {
                 sqlBuilder.append("?");
@@ -1737,9 +1745,7 @@ public class DatabaseStore {
                 }
             }
             sqlBuilder.append(")");
-
             sqlBuilder.append(" and _gid = ?");
-
             statement = connection.prepareStatement(sqlBuilder.toString());
 
             int index = 1;
@@ -1751,36 +1757,14 @@ public class DatabaseStore {
                 statement.setString(index++, memberId);
             }
             statement.setString(index++, groupId);
-
             int count = statement.executeUpdate();
             LOG.info("Update rows {}", count);
-
-            String sql = "update t_group set `_member_count` = `_member_count` - ?, `_member_dt` = ? , `_dt` = ? where `_gid` = ?";
-
-            statement2 = connection.prepareStatement(sql);
-            index = 1;
-            statement2.setInt(index++, count);
-            statement2.setLong(index++, current);
-            statement2.setLong(index++, current);
-            statement2.setString(index++, groupId);
-            statement2.executeUpdate();
-            connection.commit();
-            connection.setAutoCommit(true);
         } catch (SQLException e) {
             // TODO Auto-generated catch block
-            if (connection != null) {
-                try {
-                    connection.commit();
-                    connection.setAutoCommit(true);
-                } catch (SQLException e1) {
-                    e1.printStackTrace();
-                }
-            }
             e.printStackTrace();
             Utility.printExecption(LOG, e, RDBS_Exception);
         } finally {
             DBUtil.closeDB(connection, statement);
-            DBUtil.closeDB(connection, statement2);
         }
         return 0;
     }
diff --git a/broker/src/main/java/io/moquette/persistence/MemoryMessagesStore.java b/broker/src/main/java/io/moquette/persistence/MemoryMessagesStore.java
index cb8f3422..ff1614a4 100755
--- a/broker/src/main/java/io/moquette/persistence/MemoryMessagesStore.java
+++ b/broker/src/main/java/io/moquette/persistence/MemoryMessagesStore.java
@@ -1146,26 +1146,11 @@ public class MemoryMessagesStore implements IMessagesStore {
             }
         }
 
-        for (WFCMessage.GroupMember member : members) {
-            if (newInviteUsers.contains(member.getMemberId())) {
-                groupMembers.remove(groupId, member);
-            }
-        }
-
-        for (WFCMessage.GroupMember member : memberList) {
-            groupMembers.put(groupId, member);
-        }
-
-        int count = 0;
-        for (WFCMessage.GroupMember member : groupMembers.get(groupId)) {
-            if (member.getType() != GroupMemberType_Removed) {
-                count++;
-            }
-        }
-
-        mIMap.put(groupId, groupInfo.toBuilder().setMemberUpdateDt(updateDt).setUpdateDt(updateDt).setMemberCount(count).build());
         databaseStore.persistGroupMember(groupId, memberList);
-        databaseStore.updateGroupMemberCountDt(groupId, count, updateDt);
+        databaseStore.updateGroupMemberCountDt(groupId);
+
+        groupMembers.remove(groupId);
+        mIMap.evict(groupId);
 
         List<String> memberIds = new ArrayList<>();
         for (WFCMessage.GroupMember member : memberList) {
@@ -1191,12 +1176,12 @@ public class MemoryMessagesStore implements IMessagesStore {
     void removeGroupMember(String groupId, List<String> memberIds) {
         HazelcastInstance hzInstance = m_Server.getHazelcastInstance();
         databaseStore.removeGroupMember(groupId, memberIds);
+        databaseStore.updateGroupMemberCountDt(groupId);
 
         MultiMap<String, WFCMessage.GroupMember> groupMembers = hzInstance.getMultiMap(GROUP_MEMBERS);
         groupMembers.remove(groupId);
         IMap<String, WFCMessage.GroupInfo> mIMap = hzInstance.getMap(GROUPS_MAP);
         mIMap.evict(groupId);
-
     }
 
     void removeFavGroup(String groupId, List<String> memberIds) {
@@ -1384,8 +1369,6 @@ public class MemoryMessagesStore implements IMessagesStore {
             }
         }
 
-
-
         WFCMessage.GroupInfo.Builder newInfoBuilder = oldInfo.toBuilder();
 
         if (modifyType == Modify_Group_Name)
@@ -1407,7 +1390,8 @@ public class MemoryMessagesStore implements IMessagesStore {
 
 
         newInfoBuilder.setUpdateDt(System.currentTimeMillis());
-        mIMap.put(groupId, newInfoBuilder.build());
+        databaseStore.persistGroupInfo(newInfoBuilder.build());
+        mIMap.evict(groupId);
 
         if (modifyType == Modify_Group_Mute) {
             if (newInfoBuilder.getMute() > 0) {
@@ -1488,7 +1472,7 @@ public class MemoryMessagesStore implements IMessagesStore {
                 groupMembers.remove(groupId, member);
                 member = member.toBuilder().setAlias(alias).setUpdateDt(updateDt).build();
                 databaseStore.persistGroupMember(groupId, Arrays.asList(member));
-                databaseStore.updateGroupMemberCountDt(groupId, -1, updateDt);
+                databaseStore.updateGroupMemberDt(groupId, updateDt);
                 groupMembers.put(groupId, member);
 
                 mIMap.set(groupId, groupInfo.toBuilder().setUpdateDt(updateDt).setMemberUpdateDt(updateDt).build());
@@ -1692,11 +1676,10 @@ public class MemoryMessagesStore implements IMessagesStore {
                 member = member.toBuilder().setType(type == 0 ? ProtoConstants.GroupMemberType.GroupMemberType_Normal : ProtoConstants.GroupMemberType.GroupMemberType_Manager).setUpdateDt(updateDt).build();
                 databaseStore.persistGroupMember(groupId, Arrays.asList(member));
                 groupMembers.put(groupId, member);
-//                userList.remove(member.getMemberId());
             }
         }
-
-        mIMap.put(groupId, groupInfo.toBuilder().setUpdateDt(updateDt).setMemberUpdateDt(updateDt).build());
+        databaseStore.persistGroupInfo(groupInfo.toBuilder().setUpdateDt(updateDt).setMemberUpdateDt(updateDt).build());
+        mIMap.evict(groupId);
 
         callbackGroupMemberEvent(operator, groupId, userList, ProtoConstants.GroupMemberUpdateEventType.Group_Member_Event_Type_Update, (type == 0 ? ProtoConstants.GroupMemberType.GroupMemberType_Normal : ProtoConstants.GroupMemberType.GroupMemberType_Manager) + "");
         return ErrorCode.ERROR_CODE_SUCCESS;