diff --git a/src/mnode/src/mgmtDb.c b/src/mnode/src/mgmtDb.c
index 67aa34e50a2f5ac577a9c4e2dc2245fb713e598a..ae241f2320704e430a792d5c56db621a8115e31c 100644
--- a/src/mnode/src/mgmtDb.c
+++ b/src/mnode/src/mgmtDb.c
@@ -913,15 +913,17 @@ static void mgmtProcessDropDbMsg(SQueuedMsg *pMsg) {
     return;
   }
 
+#if 0
   SVgObj *pVgroup = pMsg->pDb->pHead;
   if (pVgroup != NULL) {
-    mPrint("vgroup:%d, will be dropped", pVgroup->vgId);
+    mPrint("vgId:%d, will be dropped", pVgroup->vgId);
     SQueuedMsg *newMsg = mgmtCloneQueuedMsg(pMsg);
     newMsg->ahandle = pVgroup;
     newMsg->expected = pVgroup->numOfVnodes;
     mgmtDropVgroup(pVgroup, newMsg);
     return;
   }
+#endif  
 
   mTrace("db:%s, all vgroups is dropped", pMsg->pDb->name);
   mgmtDropDb(pMsg);
diff --git a/src/mnode/src/mgmtDnode.c b/src/mnode/src/mgmtDnode.c
index 019e802c75374b80205083ec138a523c8ed08f31..c7643b9bf906988bc2668f8c393a38c117b866c7 100644
--- a/src/mnode/src/mgmtDnode.c
+++ b/src/mnode/src/mgmtDnode.c
@@ -309,7 +309,7 @@ void mgmtProcessDnodeStatusMsg(SRpcMsg *rpcMsg) {
     SVgObj *pVgroup = mgmtGetVgroup(pVload->vgId);
     if (pVgroup == NULL) {
       SRpcIpSet ipSet = mgmtGetIpSetFromIp(pDnode->dnodeEp);
-      mPrint("dnode:%d, vgroup:%d not exist in mnode, drop it", pDnode->dnodeId, pVload->vgId);
+      mPrint("dnode:%d, vgId:%d not exist in mnode, drop it", pDnode->dnodeId, pVload->vgId);
       mgmtSendDropVnodeMsg(pVload->vgId, &ipSet, NULL);
     } else {
       mgmtUpdateVgroupStatus(pVgroup, pDnode, pVload);
diff --git a/src/mnode/src/mgmtTable.c b/src/mnode/src/mgmtTable.c
index 7bf93872587009ef3f2f8785e7701a433bb190a9..a1d260d1cf1d86d2e92ebefe8ce5dd331c9e9d1f 100644
--- a/src/mnode/src/mgmtTable.c
+++ b/src/mnode/src/mgmtTable.c
@@ -97,14 +97,14 @@ static int32_t mgmtChildTableActionInsert(SSdbOper *pOper) {
 
   SVgObj *pVgroup = mgmtGetVgroup(pTable->vgId);
   if (pVgroup == NULL) {
-    mError("ctable:%s, not in vgroup:%d", pTable->info.tableId, pTable->vgId);
+    mError("ctable:%s, not in vgId:%d", pTable->info.tableId, pTable->vgId);
     return TSDB_CODE_INVALID_VGROUP_ID;
   }
   mgmtDecVgroupRef(pVgroup);
 
   SDbObj *pDb = mgmtGetDb(pVgroup->dbName);
   if (pDb == NULL) {
-    mError("ctable:%s, vgroup:%d not in db:%s", pTable->info.tableId, pVgroup->vgId, pVgroup->dbName);
+    mError("ctable:%s, vgId:%d not in db:%s", pTable->info.tableId, pVgroup->vgId, pVgroup->dbName);
     return TSDB_CODE_INVALID_DB;
   }
   mgmtDecDbRef(pDb);
@@ -147,7 +147,7 @@ static int32_t mgmtChildTableActionDelete(SSdbOper *pOper) {
 
   SDbObj *pDb = mgmtGetDb(pVgroup->dbName);
   if (pDb == NULL) {
-    mError("ctable:%s, vgroup:%d not in DB:%s", pTable->info.tableId, pVgroup->vgId, pVgroup->dbName);
+    mError("ctable:%s, vgId:%d not in DB:%s", pTable->info.tableId, pVgroup->vgId, pVgroup->dbName);
     return TSDB_CODE_INVALID_DB;
   }
   mgmtDecDbRef(pDb);
@@ -270,7 +270,7 @@ static int32_t mgmtChildTableActionRestored() {
 
     SVgObj *pVgroup = mgmtGetVgroup(pTable->vgId);
     if (pVgroup == NULL) {
-      mError("ctable:%s, failed to get vgroup:%d sid:%d, discard it", pTable->info.tableId, pTable->vgId, pTable->sid);
+      mError("ctable:%s, failed to get vgId:%d sid:%d, discard it", pTable->info.tableId, pTable->vgId, pTable->sid);
       pTable->vgId = 0;
       SSdbOper desc = {0};
       desc.type = SDB_OPER_LOCAL;
@@ -283,7 +283,7 @@ static int32_t mgmtChildTableActionRestored() {
     mgmtDecVgroupRef(pVgroup);
 
     if (strcmp(pVgroup->dbName, pDb->name) != 0) {
-      mError("ctable:%s, db:%s not match with vgroup:%d db:%s sid:%d, discard it",
+      mError("ctable:%s, db:%s not match with vgId:%d db:%s sid:%d, discard it",
              pTable->info.tableId, pDb->name, pTable->vgId, pVgroup->dbName, pTable->sid);
       pTable->vgId = 0;
       SSdbOper desc = {0};
@@ -296,7 +296,7 @@ static int32_t mgmtChildTableActionRestored() {
     }
 
     if (pVgroup->tableList == NULL) {
-      mError("ctable:%s, vgroup:%d tableList is null", pTable->info.tableId, pTable->vgId);
+      mError("ctable:%s, vgId:%d tableList is null", pTable->info.tableId, pTable->vgId);
       pTable->vgId = 0;
       SSdbOper desc = {0};
       desc.type = SDB_OPER_LOCAL;
@@ -1157,6 +1157,7 @@ void mgmtDropAllSuperTables(SDbObj *pDropDb) {
   mPrint("db:%s, all super tables will be dropped from sdb", pDropDb->name);
 
   while (1) {
+    pLastNode = pNode;
     pNode = mgmtGetNextSuperTable(pNode, &pTable);
     if (pTable == NULL) break;
 
@@ -1432,7 +1433,7 @@ static void mgmtProcessCreateChildTableMsg(SQueuedMsg *pMsg) {
 
   int32_t sid = taosAllocateId(pVgroup->idPool);
   if (sid <= 0) {
-    mTrace("tables:%s, no enough sid in vgroup:%d", pCreate->tableId, pVgroup->vgId);
+    mTrace("tables:%s, no enough sid in vgId:%d", pCreate->tableId, pVgroup->vgId);
     mgmtCreateVgroup(mgmtCloneQueuedMsg(pMsg), pMsg->pDb);
     return;
   }
@@ -1716,6 +1717,7 @@ void mgmtDropAllChildTables(SDbObj *pDropDb) {
   mPrint("db:%s, all child tables will be dropped from sdb", pDropDb->name);
 
   while (1) {
+    pLastNode = pNode;
     pNode = mgmtGetNextChildTable(pNode, &pTable);
     if (pTable == NULL) break;
 
@@ -1744,6 +1746,7 @@ static void mgmtDropAllChildTablesInStable(SSuperTableObj *pStable) {
   mPrint("stable:%s, all child tables will dropped from sdb", pStable->info.tableId, numOfTables);
 
   while (1) {
+    pLastNode = pNode;
     pNode = mgmtGetNextChildTable(pNode, &pTable);
     if (pTable == NULL) break;
 
@@ -1768,7 +1771,7 @@ static SChildTableObj* mgmtGetTableByPos(int32_t vnode, int32_t sid) {
   SVgObj *pVgroup = mgmtGetVgroup(vnode);
   if (pVgroup == NULL) return NULL;
 
-  SChildTableObj *pTable = pVgroup->tableList[sid];
+  SChildTableObj *pTable = pVgroup->tableList[sid - 1];
   mgmtIncTableRef((STableObj *)pTable);
 
   mgmtDecVgroupRef(pVgroup);
@@ -1852,7 +1855,7 @@ static void mgmtProcessDropChildTableRsp(SRpcMsg *rpcMsg) {
   }
 
   if (queueMsg->pVgroup->numOfTables <= 0) {
-    mPrint("vgroup:%d, all tables is dropped, drop vgroup", queueMsg->pVgroup->vgId);
+    mPrint("vgId:%d, all tables is dropped, drop vgroup", queueMsg->pVgroup->vgId);
     mgmtDropVgroup(queueMsg->pVgroup, NULL);
   }
 
diff --git a/src/mnode/src/mgmtVgroup.c b/src/mnode/src/mgmtVgroup.c
index b6d66ec0333e41f44f7f856b4d8c83f7e8635af1..d2580fc4ca525704270e2f0bf439edd88fa72cc6 100644
--- a/src/mnode/src/mgmtVgroup.c
+++ b/src/mnode/src/mgmtVgroup.c
@@ -76,13 +76,13 @@ static int32_t mgmtVgroupActionInsert(SSdbOper *pOper) {
   int32_t size = sizeof(SChildTableObj *) * pDb->cfg.maxTables;
   pVgroup->tableList = calloc(pDb->cfg.maxTables, sizeof(SChildTableObj *));
   if (pVgroup->tableList == NULL) {
-    mError("vgroup:%d, failed to malloc(size:%d) for the tableList of vgroups", pVgroup->vgId, size);
+    mError("vgId:%d, failed to malloc(size:%d) for the tableList of vgroups", pVgroup->vgId, size);
     return -1;
   }
 
   pVgroup->idPool = taosInitIdPool(pDb->cfg.maxTables);
   if (pVgroup->idPool == NULL) {
-    mError("vgroup:%d, failed to taosInitIdPool for vgroups", pVgroup->vgId);
+    mError("vgId:%d, failed to taosInitIdPool for vgroups", pVgroup->vgId);
     tfree(pVgroup->tableList);
     return -1;
   }
@@ -103,7 +103,7 @@ static int32_t mgmtVgroupActionInsert(SSdbOper *pOper) {
 
 static int32_t mgmtVgroupActionDelete(SSdbOper *pOper) {
   SVgObj *pVgroup = pOper->pObj;
-  
+
   if (pVgroup->pDb != NULL) {
     mgmtRemoveVgroupFromDb(pVgroup);
   }
@@ -150,7 +150,7 @@ static int32_t mgmtVgroupActionUpdate(SSdbOper *pOper) {
   SDbObj *pDb = pVgroup->pDb;
   if (pDb != NULL) {
     if (pDb->cfg.maxTables != oldTables) {
-      mPrint("vgroup:%d tables change from %d to %d", pVgroup->vgId, oldTables, pDb->cfg.maxTables);
+      mPrint("vgId:%d tables change from %d to %d", pVgroup->vgId, oldTables, pDb->cfg.maxTables);
       taosUpdateIdPool(pVgroup->idPool, pDb->cfg.maxTables);
       int32_t size = sizeof(SChildTableObj *) * pDb->cfg.maxTables;
       pVgroup->tableList = (SChildTableObj **)realloc(pVgroup->tableList, size);
@@ -158,7 +158,7 @@ static int32_t mgmtVgroupActionUpdate(SSdbOper *pOper) {
   }
 
   mgmtDecVgroupRef(pVgroup);
-  mTrace("vgroup:%d, is updated, tables:%d numOfVnode:%d", pVgroup->vgId, pDb->cfg.maxTables, pVgroup->numOfVnodes);
+  mTrace("vgId:%d, is updated, tables:%d numOfVnode:%d", pVgroup->vgId, pDb->cfg.maxTables, pVgroup->numOfVnodes);
   return TSDB_CODE_SUCCESS;
 }
 
@@ -264,7 +264,7 @@ void mgmtUpdateVgroupStatus(SVgObj *pVgroup, SDnodeObj *pDnode, SVnodeLoad *pVlo
 
   if (!dnodeExist) {
     SRpcIpSet ipSet = mgmtGetIpSetFromIp(pDnode->dnodeEp);
-    mError("vgroup:%d, dnode:%d not exist in mnode, drop it", pVload->vgId, pDnode->dnodeId);
+    mError("vgId:%d, dnode:%d not exist in mnode, drop it", pVload->vgId, pDnode->dnodeId);
     mgmtSendDropVnodeMsg(pVload->vgId, &ipSet, NULL);
     return;
   }
@@ -276,7 +276,7 @@ void mgmtUpdateVgroupStatus(SVgObj *pVgroup, SDnodeObj *pDnode, SVnodeLoad *pVlo
   }
 
   if (pVload->cfgVersion != pVgroup->pDb->cfgVersion || pVload->replica != pVgroup->numOfVnodes) {
-    mError("dnode:%d, vgroup:%d, vnode cfgVersion:%d repica:%d not match with mgmt cfgVersion:%d replica:%d",
+    mError("dnode:%d, vgId:%d, vnode cfgVersion:%d repica:%d not match with mgmt cfgVersion:%d replica:%d",
            pDnode->dnodeId, pVload->vgId, pVload->cfgVersion, pVload->replica, pVgroup->pDb->cfgVersion,
            pVgroup->numOfVnodes);
     mgmtSendCreateVgroupMsg(pVgroup, NULL);
@@ -320,9 +320,9 @@ void mgmtCreateVgroup(SQueuedMsg *pMsg, SDbObj *pDb) {
     return;
   }
 
-  mPrint("vgroup:%d, is created in mnode, db:%s replica:%d", pVgroup->vgId, pDb->name, pVgroup->numOfVnodes);
+  mPrint("vgId:%d, is created in mnode, db:%s replica:%d", pVgroup->vgId, pDb->name, pVgroup->numOfVnodes);
   for (int32_t i = 0; i < pVgroup->numOfVnodes; ++i) {
-    mPrint("vgroup:%d, index:%d, dnode:%d", pVgroup->vgId, i, pVgroup->vnodeGid[i].dnodeId);
+    mPrint("vgId:%d, index:%d, dnode:%d", pVgroup->vgId, i, pVgroup->vnodeGid[i].dnodeId);
   }
 
   pMsg->ahandle = pVgroup;
@@ -334,7 +334,7 @@ void mgmtDropVgroup(SVgObj *pVgroup, void *ahandle) {
   if (ahandle != NULL) {
     mgmtSendDropVgroupMsg(pVgroup, ahandle);
   } else {
-    mTrace("vgroup:%d, replica:%d is deleting from sdb", pVgroup->vgId, pVgroup->numOfVnodes);
+    mTrace("vgId:%d, replica:%d is deleting from sdb", pVgroup->vgId, pVgroup->numOfVnodes);
     mgmtSendDropVgroupMsg(pVgroup, NULL);
     SSdbOper oper = {
       .type = SDB_OPER_GLOBAL,
@@ -509,25 +509,31 @@ int32_t mgmtRetrieveVgroups(SShowObj *pShow, char *data, int32_t rows, void *pCo
 }
 
 void mgmtAddTableIntoVgroup(SVgObj *pVgroup, SChildTableObj *pTable) {
-  if (pTable->sid >= 0 && pVgroup->tableList[pTable->sid] == NULL) {
-    pVgroup->tableList[pTable->sid] = pTable;
+  if (pTable->sid >= 1 && pVgroup->tableList[pTable->sid - 1] == NULL) {
+    pVgroup->tableList[pTable->sid - 1] = pTable;
     taosIdPoolMarkStatus(pVgroup->idPool, pTable->sid);
     pVgroup->numOfTables++;
   }
   
-  if (pVgroup->numOfTables >= pVgroup->pDb->cfg.maxTables)
+  if (pVgroup->numOfTables >= pVgroup->pDb->cfg.maxTables) {
     mgmtAddVgroupIntoDbTail(pVgroup);
+  }
+
+  mgmtIncVgroupRef(pVgroup);
 }
 
 void mgmtRemoveTableFromVgroup(SVgObj *pVgroup, SChildTableObj *pTable) {
-  if (pTable->sid >= 0 && pVgroup->tableList[pTable->sid] != NULL) {
-    pVgroup->tableList[pTable->sid] = NULL;
+  if (pTable->sid >= 1 && pVgroup->tableList[pTable->sid - 1] != NULL) {
+    pVgroup->tableList[pTable->sid - 1] = NULL;
     taosFreeId(pVgroup->idPool, pTable->sid);
     pVgroup->numOfTables--;
   }
 
-  if (pVgroup->numOfTables >= pVgroup->pDb->cfg.maxTables)
-    mgmtAddVgroupIntoDbTail(pVgroup);
+  if (pVgroup->numOfTables == 0) {
+    mgmtRemoveVgroupFromDb(pVgroup);
+  }
+
+  mgmtDecVgroupRef(pVgroup);
 }
 
 SMDCreateVnodeMsg *mgmtBuildCreateVnodeMsg(SVgObj *pVgroup) {
@@ -592,7 +598,7 @@ SRpcIpSet mgmtGetIpSetFromIp(char *ep) {
 }
 
 void mgmtSendCreateVnodeMsg(SVgObj *pVgroup, SRpcIpSet *ipSet, void *ahandle) {
-  mTrace("vgroup:%d, send create vnode:%d msg, ahandle:%p", pVgroup->vgId, pVgroup->vgId, ahandle);
+  mTrace("vgId:%d, send create vnode:%d msg, ahandle:%p", pVgroup->vgId, pVgroup->vgId, ahandle);
   SMDCreateVnodeMsg *pCreate = mgmtBuildCreateVnodeMsg(pVgroup);
   SRpcMsg rpcMsg = {
     .handle  = ahandle,
@@ -605,7 +611,7 @@ void mgmtSendCreateVnodeMsg(SVgObj *pVgroup, SRpcIpSet *ipSet, void *ahandle) {
 }
 
 void mgmtSendCreateVgroupMsg(SVgObj *pVgroup, void *ahandle) {
-  mTrace("vgroup:%d, send create all vnodes msg, ahandle:%p", pVgroup->vgId, ahandle);
+  mTrace("vgId:%d, send create all vnodes msg, ahandle:%p", pVgroup->vgId, ahandle);
   for (int32_t i = 0; i < pVgroup->numOfVnodes; ++i) {
     SRpcIpSet ipSet = mgmtGetIpSetFromIp(pVgroup->vnodeGid[i].pDnode->dnodeEp);
     mgmtSendCreateVnodeMsg(pVgroup, &ipSet, ahandle);
@@ -623,7 +629,7 @@ static void mgmtProcessCreateVnodeRsp(SRpcMsg *rpcMsg) {
   }
 
   SVgObj *pVgroup = queueMsg->ahandle;
-  mTrace("vgroup:%d, create vnode rsp received, result:%s received:%d successed:%d expected:%d, thandle:%p ahandle:%p",
+  mTrace("vgId:%d, create vnode rsp received, result:%s received:%d successed:%d expected:%d, thandle:%p ahandle:%p",
          pVgroup->vgId, tstrerror(rpcMsg->code), queueMsg->received, queueMsg->successed, queueMsg->expected,
          queueMsg->thandle, rpcMsg->handle);
 
@@ -658,7 +664,7 @@ static SMDDropVnodeMsg *mgmtBuildDropVnodeMsg(int32_t vgId) {
 }
 
 void mgmtSendDropVnodeMsg(int32_t vgId, SRpcIpSet *ipSet, void *ahandle) {
-  mTrace("vgroup:%d, send drop vnode msg, ahandle:%p", vgId, ahandle);
+  mTrace("vgId:%d, send drop vnode msg, ahandle:%p", vgId, ahandle);
   SMDDropVnodeMsg *pDrop = mgmtBuildDropVnodeMsg(vgId);
   SRpcMsg rpcMsg = {
       .handle  = ahandle,
@@ -671,7 +677,7 @@ void mgmtSendDropVnodeMsg(int32_t vgId, SRpcIpSet *ipSet, void *ahandle) {
 }
 
 static void mgmtSendDropVgroupMsg(SVgObj *pVgroup, void *ahandle) {
-  mTrace("vgroup:%d, send drop all vnodes msg, ahandle:%p", pVgroup->vgId, ahandle);
+  mTrace("vgId:%d, send drop all vnodes msg, ahandle:%p", pVgroup->vgId, ahandle);
   for (int32_t i = 0; i < pVgroup->numOfVnodes; ++i) {
     SRpcIpSet ipSet = mgmtGetIpSetFromIp(pVgroup->vnodeGid[i].pDnode->dnodeEp);
     mgmtSendDropVnodeMsg(pVgroup->vgId, &ipSet, ahandle);
@@ -679,7 +685,7 @@ static void mgmtSendDropVgroupMsg(SVgObj *pVgroup, void *ahandle) {
 }
 
 static void mgmtProcessDropVnodeRsp(SRpcMsg *rpcMsg) {
-  mTrace("drop vnode rsp is received");
+  mTrace("drop vnode rsp is received, handle:%p", rpcMsg->handle);
   if (rpcMsg->handle == NULL) return;
 
   SQueuedMsg *queueMsg = rpcMsg->handle;
@@ -690,7 +696,7 @@ static void mgmtProcessDropVnodeRsp(SRpcMsg *rpcMsg) {
   }
 
   SVgObj *pVgroup = queueMsg->ahandle;
-  mTrace("vgroup:%d, drop vnode rsp received, result:%s received:%d successed:%d expected:%d, thandle:%p ahandle:%p",
+  mTrace("vgId:%d, drop vnode rsp received, result:%s received:%d successed:%d expected:%d, thandle:%p ahandle:%p",
          pVgroup->vgId, tstrerror(rpcMsg->code), queueMsg->received, queueMsg->successed, queueMsg->expected,
          queueMsg->thandle, rpcMsg->handle);
 
@@ -774,6 +780,7 @@ void mgmtDropAllDbVgroups(SDbObj *pDropDb) {
 
   mPrint("db:%s, all vgroups will be dropped from sdb", pDropDb->name);
   while (1) {
+    pLastNode = pNode;
     pNode = mgmtGetNextVgroup(pNode, &pVgroup);
     if (pVgroup == NULL) break;