diff --git a/source/client/test/clientTests.cpp b/source/client/test/clientTests.cpp
index a3b1c4f7791879361630566cc2aead282b0e63a2..59c931d9aa8b30bce9933c322db2bf50c8611093 100644
--- a/source/client/test/clientTests.cpp
+++ b/source/client/test/clientTests.cpp
@@ -912,7 +912,7 @@ TEST(clientCase, subscription_test) {
   tmq_conf_t* conf = tmq_conf_new();
   tmq_conf_set(conf, "enable.auto.commit", "true");
   tmq_conf_set(conf, "auto.commit.interval.ms", "1000");
-  tmq_conf_set(conf, "group.id", "consumer_group");
+  tmq_conf_set(conf, "group.id", "cgrpName");
   tmq_conf_set(conf, "td.connect.user", "root");
   tmq_conf_set(conf, "td.connect.pass", "taosdata");
   tmq_conf_set(conf, "auto.offset.reset", "earliest");
diff --git a/source/dnode/mnode/impl/src/mndConsumer.c b/source/dnode/mnode/impl/src/mndConsumer.c
index 369c7fabd904300ad4b53597f49352800a625bdb..01d89bc718c53d66441dd46318a794f8da4e0553 100644
--- a/source/dnode/mnode/impl/src/mndConsumer.c
+++ b/source/dnode/mnode/impl/src/mndConsumer.c
@@ -100,8 +100,8 @@ static int32_t mndProcessConsumerLostMsg(SRpcMsg *pMsg) {
     return 0;
   }
 
-  mInfo("receive consumer lost msg, consumer id %" PRId64 ", status %s", pLostMsg->consumerId,
-        mndConsumerStatusName(pConsumer->status));
+  mInfo("process consumer lost msg, consumer:0x%" PRIx64 " status:%d(%s)", pLostMsg->consumerId,
+        pConsumer->status, mndConsumerStatusName(pConsumer->status));
 
   if (pConsumer->status != MQ_CONSUMER_STATUS__READY) {
     mndReleaseConsumer(pMnode, pConsumer);
@@ -114,9 +114,17 @@ static int32_t mndProcessConsumerLostMsg(SRpcMsg *pMsg) {
   mndReleaseConsumer(pMnode, pConsumer);
 
   STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_NOTHING, pMsg, "lost-csm");
-  if (pTrans == NULL) goto FAIL;
-  if (mndSetConsumerCommitLogs(pMnode, pTrans, pConsumerNew) != 0) goto FAIL;
-  if (mndTransPrepare(pMnode, pTrans) != 0) goto FAIL;
+  if (pTrans == NULL) {
+    goto FAIL;
+  }
+
+  if (mndSetConsumerCommitLogs(pMnode, pTrans, pConsumerNew) != 0) {
+    goto FAIL;
+  }
+
+  if (mndTransPrepare(pMnode, pTrans) != 0) {
+    goto FAIL;
+  }
 
   tDeleteSMqConsumerObj(pConsumerNew);
   taosMemoryFree(pConsumerNew);
@@ -135,8 +143,8 @@ static int32_t mndProcessConsumerRecoverMsg(SRpcMsg *pMsg) {
   SMqConsumerObj        *pConsumer = mndAcquireConsumer(pMnode, pRecoverMsg->consumerId);
   ASSERT(pConsumer);
 
-  mInfo("receive consumer recover msg, consumer id %" PRId64 ", status %s", pRecoverMsg->consumerId,
-        mndConsumerStatusName(pConsumer->status));
+  mInfo("receive consumer recover msg, consumer:0x%" PRIx64 " status:%d(%s)", pRecoverMsg->consumerId,
+        pConsumer->status, mndConsumerStatusName(pConsumer->status));
 
   if (pConsumer->status != MQ_CONSUMER_STATUS__LOST_REBD) {
     mndReleaseConsumer(pMnode, pConsumer);
@@ -150,7 +158,10 @@ static int32_t mndProcessConsumerRecoverMsg(SRpcMsg *pMsg) {
   mndReleaseConsumer(pMnode, pConsumer);
 
   STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_RETRY, TRN_CONFLICT_NOTHING, pMsg, "recover-csm");
-  if (pTrans == NULL) goto FAIL;
+  if (pTrans == NULL) {
+    goto FAIL;
+  }
+
   if (mndSetConsumerCommitLogs(pMnode, pTrans, pConsumerNew) != 0) goto FAIL;
   if (mndTransPrepare(pMnode, pTrans) != 0) goto FAIL;
 
@@ -244,21 +255,24 @@ static int32_t mndProcessMqTimerMsg(SRpcMsg *pMsg) {
 
     int32_t hbStatus = atomic_add_fetch_32(&pConsumer->hbStatus, 1);
     int32_t status = atomic_load_32(&pConsumer->status);
-    if (status == MQ_CONSUMER_STATUS__READY && hbStatus > MND_CONSUMER_LOST_HB_CNT) {
-      SMqConsumerLostMsg *pLostMsg = rpcMallocCont(sizeof(SMqConsumerLostMsg));
-
-      pLostMsg->consumerId = pConsumer->consumerId;
-      SRpcMsg rpcMsg = {
-          .msgType = TDMT_MND_TMQ_CONSUMER_LOST,
-          .pCont = pLostMsg,
-          .contLen = sizeof(SMqConsumerLostMsg),
-      };
-      tmsgPutToQueue(&pMnode->msgCb, WRITE_QUEUE, &rpcMsg);
-    }
+
+    mDebug("check for consumer:0x%"PRIx64" status:%d(%s), sub-time:%"PRId64", uptime:%"PRId64,
+        pConsumer->consumerId, status, mndConsumerStatusName(status), pConsumer->subscribeTime, pConsumer->upTime);
 
     if (status == MQ_CONSUMER_STATUS__READY) {
-      // do nothing
+      if (hbStatus > MND_CONSUMER_LOST_HB_CNT) {
+        SMqConsumerLostMsg *pLostMsg = rpcMallocCont(sizeof(SMqConsumerLostMsg));
+
+        pLostMsg->consumerId = pConsumer->consumerId;
+        SRpcMsg rpcMsg = {
+            .msgType = TDMT_MND_TMQ_CONSUMER_LOST,
+            .pCont = pLostMsg,
+            .contLen = sizeof(SMqConsumerLostMsg),
+        };
+        tmsgPutToQueue(&pMnode->msgCb, WRITE_QUEUE, &rpcMsg);
+      }
     } else if (status == MQ_CONSUMER_STATUS__LOST_REBD) {
+      // if the client is lost longer than one day, clear it. Otherwise, do nothing about the lost consumers.
       if (hbStatus > MND_CONSUMER_LOST_CLEAR_THRESHOLD) {
         SMqConsumerClearMsg *pClearMsg = rpcMallocCont(sizeof(SMqConsumerClearMsg));
 
@@ -379,11 +393,18 @@ static int32_t mndProcessAskEpReq(SRpcMsg *pMsg) {
 
   SMqConsumerObj *pConsumer = mndAcquireConsumer(pMnode, consumerId);
   if (pConsumer == NULL) {
+    mError("consumer:0x%" PRIx64 " group:%s not exists in sdb", consumerId, req.cgroup);
     terrno = TSDB_CODE_MND_CONSUMER_NOT_EXIST;
     return -1;
   }
 
-  ASSERT(strcmp(req.cgroup, pConsumer->cgroup) == 0);
+  int32_t ret = strncmp(req.cgroup, pConsumer->cgroup, tListLen(pConsumer->cgroup));
+  if (ret != 0) {
+    mError("consumer:0x%" PRIx64 " group:%s not consistent with data in sdb, saved cgroup:%s", consumerId, req.cgroup,
+           pConsumer->cgroup);
+    terrno = TSDB_CODE_MND_CONSUMER_NOT_EXIST;
+    return -1;
+  }
 
   atomic_store_32(&pConsumer->hbStatus, 0);
 
@@ -392,7 +413,7 @@ static int32_t mndProcessAskEpReq(SRpcMsg *pMsg) {
 
 #if 1
   if (status == MQ_CONSUMER_STATUS__LOST_REBD) {
-    mInfo("try to recover consumer:0x%"PRIx64 "", consumerId);
+    mInfo("try to recover consumer:0x%"PRIx64, consumerId);
     SMqConsumerRecoverMsg *pRecoverMsg = rpcMallocCont(sizeof(SMqConsumerRecoverMsg));
 
     pRecoverMsg->consumerId = consumerId;
@@ -401,6 +422,7 @@ static int32_t mndProcessAskEpReq(SRpcMsg *pMsg) {
         .pCont = pRecoverMsg,
         .contLen = sizeof(SMqConsumerRecoverMsg),
     };
+
     tmsgPutToQueue(&pMnode->msgCb, WRITE_QUEUE, &pRpcMsg);
   }
 #endif
@@ -416,7 +438,7 @@ static int32_t mndProcessAskEpReq(SRpcMsg *pMsg) {
   // 2. check epoch, only send ep info when epochs do not match
   if (epoch != serverEpoch) {
     taosRLockLatch(&pConsumer->lock);
-    mInfo("process ask ep, consumer:%" PRId64 "(epoch %d), server epoch %d", consumerId, epoch, serverEpoch);
+    mInfo("process ask ep, consumer:0x%" PRIx64 "(epoch %d) update with server epoch %d", consumerId, epoch, serverEpoch);
     int32_t numOfTopics = taosArrayGetSize(pConsumer->currentTopics);
 
     rsp.topics = taosArrayInit(numOfTopics, sizeof(SMqSubTopicEp));
@@ -426,7 +448,7 @@ static int32_t mndProcessAskEpReq(SRpcMsg *pMsg) {
       goto FAIL;
     }
 
-    // handle all topic subscribed by the consumer
+    // handle all topics subscribed by this consumer
     for (int32_t i = 0; i < numOfTopics; i++) {
       char            *topic = taosArrayGetP(pConsumer->currentTopics, i);
       SMqSubscribeObj *pSub = mndAcquireSubscribe(pMnode, pConsumer->cgroup, topic);
@@ -455,6 +477,7 @@ static int32_t mndProcessAskEpReq(SRpcMsg *pMsg) {
       SMqConsumerEp *pConsumerEp = taosHashGet(pSub->consumerHash, &consumerId, sizeof(int64_t));
       int32_t        vgNum = taosArrayGetSize(pConsumerEp->vgs);
 
+      // this customer assigned vgroups
       topicEp.vgs = taosArrayInit(vgNum, sizeof(SMqSubVgEp));
       if (topicEp.vgs == NULL) {
         terrno = TSDB_CODE_OUT_OF_MEMORY;
@@ -484,6 +507,7 @@ static int32_t mndProcessAskEpReq(SRpcMsg *pMsg) {
     }
     taosRUnLockLatch(&pConsumer->lock);
   }
+
   // encode rsp
   int32_t tlen = sizeof(SMqRspHead) + tEncodeSMqAskEpRsp(NULL, &rsp);
   void   *buf = rpcMallocCont(tlen);
@@ -491,6 +515,7 @@ static int32_t mndProcessAskEpReq(SRpcMsg *pMsg) {
     terrno = TSDB_CODE_OUT_OF_MEMORY;
     return -1;
   }
+
   ((SMqRspHead *)buf)->mqMsgType = TMQ_MSG_TYPE__EP_RSP;
   ((SMqRspHead *)buf)->epoch = serverEpoch;
   ((SMqRspHead *)buf)->consumerId = pConsumer->consumerId;
@@ -506,6 +531,7 @@ static int32_t mndProcessAskEpReq(SRpcMsg *pMsg) {
   pMsg->info.rsp = buf;
   pMsg->info.rspLen = tlen;
   return 0;
+
 FAIL:
   tDeleteSMqAskEpRsp(&rsp);
   mndReleaseConsumer(pMnode, pConsumer);
@@ -547,7 +573,7 @@ int32_t mndProcessSubscribeReq(SRpcMsg *pMsg) {
 
   int32_t newTopicNum = taosArrayGetSize(newSub);
 
-  // check topic existance
+  // check topic existence
   STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_RETRY, TRN_CONFLICT_NOTHING, pMsg, "subscribe");
   if (pTrans == NULL) {
     goto _over;
@@ -718,13 +744,14 @@ CM_ENCODE_OVER:
 }
 
 SSdbRow *mndConsumerActionDecode(SSdbRaw *pRaw) {
-  terrno = TSDB_CODE_OUT_OF_MEMORY;
   SSdbRow        *pRow = NULL;
   SMqConsumerObj *pConsumer = NULL;
   void           *buf = NULL;
 
   int8_t sver = 0;
-  if (sdbGetRawSoftVer(pRaw, &sver) != 0) goto CM_DECODE_OVER;
+  if (sdbGetRawSoftVer(pRaw, &sver) != 0) {
+    goto CM_DECODE_OVER;
+  }
 
   if (sver != MND_CONSUMER_VER_NUMBER) {
     terrno = TSDB_CODE_SDB_INVALID_DATA_VER;
@@ -732,52 +759,62 @@ SSdbRow *mndConsumerActionDecode(SSdbRaw *pRaw) {
   }
 
   pRow = sdbAllocRow(sizeof(SMqConsumerObj));
-  if (pRow == NULL) goto CM_DECODE_OVER;
+  if (pRow == NULL) {
+    goto CM_DECODE_OVER;
+  }
 
   pConsumer = sdbGetRowObj(pRow);
-  if (pConsumer == NULL) goto CM_DECODE_OVER;
+  if (pConsumer == NULL) {
+    goto CM_DECODE_OVER;
+  }
 
   int32_t dataPos = 0;
   int32_t len;
   SDB_GET_INT32(pRaw, dataPos, &len, CM_DECODE_OVER);
   buf = taosMemoryMalloc(len);
-  if (buf == NULL) goto CM_DECODE_OVER;
+  if (buf == NULL) {
+    terrno = TSDB_CODE_OUT_OF_MEMORY;
+    goto CM_DECODE_OVER;
+  }
+
   SDB_GET_BINARY(pRaw, dataPos, buf, len, CM_DECODE_OVER);
   SDB_GET_RESERVE(pRaw, dataPos, MND_CONSUMER_RESERVE_SIZE, CM_DECODE_OVER);
 
   if (tDecodeSMqConsumerObj(buf, pConsumer) == NULL) {
+    terrno = TSDB_CODE_OUT_OF_MEMORY;  // TODO set correct error code
     goto CM_DECODE_OVER;
   }
-  tmsgUpdateDnodeEpSet(&pConsumer->ep);
 
-  terrno = TSDB_CODE_SUCCESS;
+  tmsgUpdateDnodeEpSet(&pConsumer->ep);
 
 CM_DECODE_OVER:
   taosMemoryFreeClear(buf);
   if (terrno != TSDB_CODE_SUCCESS) {
-    mError("consumer:%" PRId64 ", failed to decode from raw:%p since %s", pConsumer == NULL ? 0 : pConsumer->consumerId,
-           pRaw, terrstr());
+    mError("consumer:0x%" PRIx64 " failed to decode from raw:%p since %s",
+           pConsumer == NULL ? 0 : pConsumer->consumerId, pRaw, terrstr());
     taosMemoryFreeClear(pRow);
-    return NULL;
   }
 
   return pRow;
 }
 
 static int32_t mndConsumerActionInsert(SSdb *pSdb, SMqConsumerObj *pConsumer) {
-  mTrace("consumer:%" PRId64 ", perform insert action", pConsumer->consumerId);
+  mDebug("consumer:0x%" PRIx64 " cgroup:%s status:%d(%s) epoch:%d load from sdb, perform insert action",
+         pConsumer->consumerId, pConsumer->cgroup, pConsumer->status, mndConsumerStatusName(pConsumer->status),
+         pConsumer->epoch);
   pConsumer->subscribeTime = pConsumer->upTime;
   return 0;
 }
 
 static int32_t mndConsumerActionDelete(SSdb *pSdb, SMqConsumerObj *pConsumer) {
-  mTrace("consumer:%" PRId64 ", perform delete action", pConsumer->consumerId);
+  mDebug("consumer:0x%" PRIx64 " perform delete action, status:%s", pConsumer->consumerId, mndConsumerStatusName(pConsumer->status));
   tDeleteSMqConsumerObj(pConsumer);
   return 0;
 }
 
 static int32_t mndConsumerActionUpdate(SSdb *pSdb, SMqConsumerObj *pOldConsumer, SMqConsumerObj *pNewConsumer) {
-  mTrace("consumer:%" PRId64 ", perform update action", pOldConsumer->consumerId);
+  mDebug("consumer:0x%" PRIx64 " perform update action, update type:%d, subscribe-time:%"PRId64", uptime:%"PRId64,
+      pOldConsumer->consumerId, pNewConsumer->updateType, pOldConsumer->subscribeTime, pOldConsumer->upTime);
 
   taosWLockLatch(&pOldConsumer->lock);
 
@@ -817,7 +854,11 @@ static int32_t mndConsumerActionUpdate(SSdb *pSdb, SMqConsumerObj *pOldConsumer,
 
     pOldConsumer->rebalanceTime = pNewConsumer->upTime;
 
+    int32_t status = pOldConsumer->status;
     pOldConsumer->status = MQ_CONSUMER_STATUS__LOST;
+    mDebug("consumer:0x%" PRIx64 " state %s -> %s, reb-time:%" PRId64 ", reb-removed-topics:%d",
+           pOldConsumer->consumerId, mndConsumerStatusName(status), mndConsumerStatusName(pOldConsumer->status),
+           pOldConsumer->rebalanceTime, (int)taosArrayGetSize(pOldConsumer->rebRemovedTopics));
   } else if (pNewConsumer->updateType == CONSUMER_UPDATE__RECOVER) {
     ASSERT(taosArrayGetSize(pOldConsumer->currentTopics) == 0);
     ASSERT(taosArrayGetSize(pOldConsumer->rebNewTopics) == 0);
@@ -844,7 +885,8 @@ static int32_t mndConsumerActionUpdate(SSdb *pSdb, SMqConsumerObj *pOldConsumer,
     // not exist in current topic
     bool existing = false;
 #if 1
-    for (int32_t i = 0; i < taosArrayGetSize(pOldConsumer->currentTopics); i++) {
+    int32_t numOfExistedTopics = taosArrayGetSize(pOldConsumer->currentTopics);
+    for (int32_t i = 0; i < numOfExistedTopics; i++) {
       char *topic = taosArrayGetP(pOldConsumer->currentTopics, i);
       if (strcmp(topic, addedTopic) == 0) {
         existing = true;
@@ -869,27 +911,28 @@ static int32_t mndConsumerActionUpdate(SSdb *pSdb, SMqConsumerObj *pOldConsumer,
     }
 
     // set status
+    int32_t status = pOldConsumer->status;
     if (taosArrayGetSize(pOldConsumer->rebNewTopics) == 0 && taosArrayGetSize(pOldConsumer->rebRemovedTopics) == 0) {
-      if (pOldConsumer->status == MQ_CONSUMER_STATUS__MODIFY ||
-          pOldConsumer->status == MQ_CONSUMER_STATUS__MODIFY_IN_REB) {
+      if (status == MQ_CONSUMER_STATUS__MODIFY || status == MQ_CONSUMER_STATUS__MODIFY_IN_REB) {
         pOldConsumer->status = MQ_CONSUMER_STATUS__READY;
-      } else if (pOldConsumer->status == MQ_CONSUMER_STATUS__LOST_IN_REB ||
-                 pOldConsumer->status == MQ_CONSUMER_STATUS__LOST) {
+      } else if (status == MQ_CONSUMER_STATUS__LOST_IN_REB || status == MQ_CONSUMER_STATUS__LOST) {
         pOldConsumer->status = MQ_CONSUMER_STATUS__LOST_REBD;
       }
     } else {
-      if (pOldConsumer->status == MQ_CONSUMER_STATUS__MODIFY ||
-          pOldConsumer->status == MQ_CONSUMER_STATUS__MODIFY_IN_REB) {
+      if (status == MQ_CONSUMER_STATUS__MODIFY || status == MQ_CONSUMER_STATUS__MODIFY_IN_REB) {
         pOldConsumer->status = MQ_CONSUMER_STATUS__MODIFY_IN_REB;
-      } else if (pOldConsumer->status == MQ_CONSUMER_STATUS__LOST ||
-                 pOldConsumer->status == MQ_CONSUMER_STATUS__LOST_IN_REB) {
+      } else if (status == MQ_CONSUMER_STATUS__LOST || status == MQ_CONSUMER_STATUS__LOST_IN_REB) {
         pOldConsumer->status = MQ_CONSUMER_STATUS__LOST_IN_REB;
       }
     }
 
+    // the re-balance is triggered when the new consumer is launched.
     pOldConsumer->rebalanceTime = pNewConsumer->upTime;
 
     atomic_add_fetch_32(&pOldConsumer->epoch, 1);
+    mDebug("consumer:0x%" PRIx64 " state %s -> %s, new epoch:%d, reb-time:%" PRId64 ", current topics:%d",
+           pOldConsumer->consumerId, mndConsumerStatusName(status), mndConsumerStatusName(pOldConsumer->status),
+           pOldConsumer->epoch, pOldConsumer->rebalanceTime, (int)taosArrayGetSize(pOldConsumer->currentTopics));
   } else if (pNewConsumer->updateType == CONSUMER_UPDATE__REMOVE) {
     ASSERT(taosArrayGetSize(pNewConsumer->rebNewTopics) == 0);
     ASSERT(taosArrayGetSize(pNewConsumer->rebRemovedTopics) == 1);
@@ -928,27 +971,27 @@ static int32_t mndConsumerActionUpdate(SSdb *pSdb, SMqConsumerObj *pOldConsumer,
     ASSERT(i < sz);
 
     // set status
+    int32_t status = pOldConsumer->status;
     if (taosArrayGetSize(pOldConsumer->rebNewTopics) == 0 && taosArrayGetSize(pOldConsumer->rebRemovedTopics) == 0) {
-      if (pOldConsumer->status == MQ_CONSUMER_STATUS__MODIFY ||
-          pOldConsumer->status == MQ_CONSUMER_STATUS__MODIFY_IN_REB) {
+      if (status == MQ_CONSUMER_STATUS__MODIFY || status == MQ_CONSUMER_STATUS__MODIFY_IN_REB) {
         pOldConsumer->status = MQ_CONSUMER_STATUS__READY;
-      } else if (pOldConsumer->status == MQ_CONSUMER_STATUS__LOST_IN_REB ||
-                 pOldConsumer->status == MQ_CONSUMER_STATUS__LOST) {
+      } else if (status == MQ_CONSUMER_STATUS__LOST_IN_REB || status == MQ_CONSUMER_STATUS__LOST) {
         pOldConsumer->status = MQ_CONSUMER_STATUS__LOST_REBD;
       }
     } else {
-      if (pOldConsumer->status == MQ_CONSUMER_STATUS__MODIFY ||
-          pOldConsumer->status == MQ_CONSUMER_STATUS__MODIFY_IN_REB) {
+      if (status == MQ_CONSUMER_STATUS__MODIFY || status == MQ_CONSUMER_STATUS__MODIFY_IN_REB) {
         pOldConsumer->status = MQ_CONSUMER_STATUS__MODIFY_IN_REB;
-      } else if (pOldConsumer->status == MQ_CONSUMER_STATUS__LOST ||
-                 pOldConsumer->status == MQ_CONSUMER_STATUS__LOST_IN_REB) {
+      } else if (status == MQ_CONSUMER_STATUS__LOST || status == MQ_CONSUMER_STATUS__LOST_IN_REB) {
         pOldConsumer->status = MQ_CONSUMER_STATUS__LOST_IN_REB;
       }
     }
 
     pOldConsumer->rebalanceTime = pNewConsumer->upTime;
-
     atomic_add_fetch_32(&pOldConsumer->epoch, 1);
+
+    mDebug("consumer:0x%" PRIx64 " state %s -> %s, new epoch:%d, reb-time:%" PRId64 ", current topics:%d",
+           pOldConsumer->consumerId, mndConsumerStatusName(status), mndConsumerStatusName(pOldConsumer->status),
+           pOldConsumer->epoch, pOldConsumer->rebalanceTime, (int)taosArrayGetSize(pOldConsumer->currentTopics));
   }
 
   taosWUnLockLatch(&pOldConsumer->lock);
@@ -1036,8 +1079,7 @@ static int32_t mndRetrieveConsumer(SRpcMsg *pReq, SShowObj *pShow, SSDataBlock *
       if (hasTopic) {
         char        topic[TSDB_TOPIC_FNAME_LEN + VARSTR_HEADER_SIZE] = {0};
         const char *topicName = mndTopicGetShowName(taosArrayGetP(pConsumer->assignedTopics, i));
-        tstrncpy(varDataVal(topic), topicName, TSDB_TOPIC_FNAME_LEN);
-        varDataSetLen(topic, strlen(varDataVal(topic)));
+        STR_TO_VARSTR(topic, topicName);
         colDataSetVal(pColInfo, numOfRows, (const char *)topic, false);
       } else {
         colDataSetVal(pColInfo, numOfRows, NULL, true);
diff --git a/source/dnode/mnode/impl/src/mndTopic.c b/source/dnode/mnode/impl/src/mndTopic.c
index 220e3051115b26f7a8cee6eb3f8407693aa7f172..b843534fcd7d782eac154842df51e80957265abc 100644
--- a/source/dnode/mnode/impl/src/mndTopic.c
+++ b/source/dnode/mnode/impl/src/mndTopic.c
@@ -561,17 +561,17 @@ static int32_t mndProcessCreateTopicReq(SRpcMsg *pReq) {
     goto _OVER;
   }
 
-  mInfo("topic:%s, start to create, sql:%s", createTopicReq.name, createTopicReq.sql);
+  mInfo("topic:%s start to create, sql:%s", createTopicReq.name, createTopicReq.sql);
 
   if (mndCheckCreateTopicReq(&createTopicReq) != 0) {
-    mError("topic:%s, failed to create since %s", createTopicReq.name, terrstr());
+    mError("topic:%s failed to create since %s", createTopicReq.name, terrstr());
     goto _OVER;
   }
 
   pTopic = mndAcquireTopic(pMnode, createTopicReq.name);
   if (pTopic != NULL) {
     if (createTopicReq.igExists) {
-      mInfo("topic:%s, already exist, ignore exist is set", createTopicReq.name);
+      mInfo("topic:%s already exist, ignore exist is set", createTopicReq.name);
       code = 0;
       goto _OVER;
     } else {
@@ -731,8 +731,9 @@ static int32_t mndProcessDropTopicReq(SRpcMsg *pReq) {
 
   if (pTopic->ntbUid != 0) {
     // broadcast to all vnode
-    void   *pIter = NULL;
+    pIter = NULL;
     SVgObj *pVgroup = NULL;
+
     while (1) {
       pIter = sdbFetch(pSdb, SDB_VGROUP, pIter, (void **)&pVgroup);
       if (pIter == NULL) break;
diff --git a/source/dnode/vnode/src/tq/tqRead.c b/source/dnode/vnode/src/tq/tqRead.c
index 04c2ed3f382612457d2796fc0ec2773ebe31bfa9..841dc29731b38a2e4d63e5c27aa351c31fe14b18 100644
--- a/source/dnode/vnode/src/tq/tqRead.c
+++ b/source/dnode/vnode/src/tq/tqRead.c
@@ -746,7 +746,10 @@ int32_t tqUpdateTbUidList(STQ* pTq, const SArray* tbUidList, bool isAdd) {
   void* pIter = NULL;
   while (1) {
     pIter = taosHashIterate(pTq->pHandle, pIter);
-    if (pIter == NULL) break;
+    if (pIter == NULL) {
+      break;
+    }
+
     STqHandle* pExec = (STqHandle*)pIter;
     if (pExec->execHandle.subType == TOPIC_SUB_TYPE__COLUMN) {
       int32_t code = qUpdateQualifiedTableId(pExec->execHandle.task, tbUidList, isAdd);
diff --git a/source/libs/executor/src/executor.c b/source/libs/executor/src/executor.c
index 8f8b32ff07f83f92475d72712dfe7b015a72b6a7..19c9c6f97d2722058dbc90d8973eedee7bb51700 100644
--- a/source/libs/executor/src/executor.c
+++ b/source/libs/executor/src/executor.c
@@ -279,11 +279,15 @@ qTaskInfo_t qCreateStreamExecTaskInfo(void* msg, SReadHandle* readers) {
 
 static SArray* filterUnqualifiedTables(const SStreamScanInfo* pScanInfo, const SArray* tableIdList, const char* idstr) {
   SArray* qa = taosArrayInit(4, sizeof(tb_uid_t));
+  int32_t numOfUids = taosArrayGetSize(tableIdList);
+  if (numOfUids == 0) {
+    return qa;
+  }
 
   // let's discard the tables those are not created according to the queried super table.
   SMetaReader mr = {0};
   metaReaderInit(&mr, pScanInfo->readHandle.meta, 0);
-  for (int32_t i = 0; i < taosArrayGetSize(tableIdList); ++i) {
+  for (int32_t i = 0; i < numOfUids; ++i) {
     uint64_t* id = (uint64_t*)taosArrayGet(tableIdList, i);
 
     int32_t code = metaGetTableEntryByUid(&mr, *id);