diff --git a/src/mnode/inc/mnodeDef.h b/src/mnode/inc/mnodeDef.h
index 3154a441caeabe731fed7caa77da8c52176cd9dd..a454f413f00fa2af74a753e6bd86c8898047354e 100644
--- a/src/mnode/inc/mnodeDef.h
+++ b/src/mnode/inc/mnodeDef.h
@@ -50,8 +50,8 @@ typedef struct SDnodeObj {
   int8_t     alternativeRole;  // from dnode status msg, 0-any, 1-mgmt, 2-dnode
   int8_t     status;           // set in balance function
   int8_t     isMgmt;
-  int8_t     reserve1[14];  
-  int8_t     updateEnd[1];
+  int8_t     reserve1[11];  
+  int8_t     updateEnd[4];
   int32_t    refCount;
   uint32_t   moduleStatus;
   uint32_t   lastReboot;       // time stamp for last reboot
@@ -68,8 +68,8 @@ typedef struct SMnodeObj {
   int32_t    mnodeId;
   int8_t     reserved0[4];
   int64_t    createdTime;
-  int8_t     reserved1[7];
-  int8_t     updateEnd[1];
+  int8_t     reserved1[4];
+  int8_t     updateEnd[4];
   int32_t    refCount;
   int8_t     role;
   int8_t     reserved2[3];
@@ -90,8 +90,7 @@ typedef struct SSuperTableObj {
   int32_t    tversion;
   int32_t    numOfColumns;
   int32_t    numOfTags;
-  int8_t     reserved1[3];
-  int8_t     updateEnd[1];
+  int8_t     updateEnd[4];
   int32_t    refCount;
   int32_t    numOfTables;
   SSchema *  schema;
@@ -111,8 +110,7 @@ typedef struct {
   int32_t    sid;
   int32_t    vgId;
   int32_t    sqlLen;
-  int8_t     updateEnd[1];
-  int8_t     reserved1[1]; 
+  int8_t     updateEnd[4];
   int32_t    refCount;
   char*      sql;          //used by normal table
   SSchema*   schema;       //used by normal table
@@ -138,8 +136,8 @@ typedef struct SVgObj {
   int8_t         status;
   int8_t         reserved0[4];
   SVnodeGid      vnodeGid[TSDB_MAX_REPLICA];
-  int8_t         reserved1[7];
-  int8_t         updateEnd[1];
+  int8_t         reserved1[4];
+  int8_t         updateEnd[4];
   int32_t        refCount;
   int32_t        numOfTables;
   int64_t        totalStorage;
@@ -176,8 +174,8 @@ typedef struct SDbObj {
   int32_t cfgVersion;
   SDbCfg  cfg;
   int8_t  status;
-  int8_t  reserved1[14];
-  int8_t  updateEnd[1];
+  int8_t  reserved1[11];
+  int8_t  updateEnd[4];
   int32_t refCount;
   int32_t numOfVgroups;
   int32_t numOfTables;
@@ -196,8 +194,8 @@ typedef struct SUserObj {
   int64_t           createdTime;
   int8_t            superAuth;
   int8_t            writeAuth;
-  int8_t            reserved[13];
-  int8_t            updateEnd[1];
+  int8_t            reserved[10];
+  int8_t            updateEnd[4];
   int32_t           refCount;
   struct SAcctObj * pAcct;
 } SUserObj;
@@ -228,11 +226,11 @@ typedef struct SAcctObj {
   int64_t   createdTime;
   int32_t   acctId;
   int8_t    status;
-  int8_t    reserved0[10];
-  int8_t    updateEnd[1];
-  SAcctInfo acctInfo;
+  int8_t    reserved0[7];
+  int8_t    updateEnd[4];
   int32_t   refCount;
   int8_t    reserved1[4];
+  SAcctInfo acctInfo;
   pthread_mutex_t  mutex;
 } SAcctObj;
 
diff --git a/src/mnode/src/mnodeDb.c b/src/mnode/src/mnodeDb.c
index fb97d6f3802689a7c6cbe1cf09f12e07629eaf1c..a159e98ed5e9efb086608e7e1b3965bb714eb292 100644
--- a/src/mnode/src/mnodeDb.c
+++ b/src/mnode/src/mnodeDb.c
@@ -67,8 +67,11 @@ static int32_t mnodeDbActionInsert(SSdbOper *pOper) {
   SAcctObj *pAcct = mnodeGetAcct(pDb->acct);
 
   pthread_mutex_init(&pDb->mutex, NULL);
+  pthread_mutex_lock(&pDb->mutex);
   pDb->vgListSize = VG_LIST_SIZE;
   pDb->vgList = calloc(pDb->vgListSize, sizeof(SVgObj *));
+  pthread_mutex_unlock(&pDb->mutex);
+
   pDb->numOfVgroups = 0;
   pDb->numOfTables = 0;
   pDb->numOfSuperTables = 0;
@@ -395,8 +398,8 @@ static int32_t mnodeCreateDb(SAcctObj *pAcct, SCMCreateDbMsg *pCreate, void *pMs
 
   code = sdbInsertRow(&oper);
   if (code != TSDB_CODE_SUCCESS) {
-    mnodeDestroyDb(pDb);
     mLInfo("db:%s, failed to create, reason:%s", pDb->name, tstrerror(code));
+    mnodeDestroyDb(pDb);
     return code;
   } else {
     return TSDB_CODE_MND_ACTION_IN_PROGRESS;
@@ -605,7 +608,9 @@ static int32_t mnodeGetDbMeta(STableMetaMsg *pMeta, SShowObj *pShow, void *pConn
 
 static char *mnodeGetDbStr(char *src) {
   char *pos = strstr(src, TS_PATH_DELIMITER);
-  return ++pos;
+  if (pos != NULL) ++pos;
+
+  return pos;
 }
 
 static int32_t mnodeRetrieveDbs(SShowObj *pShow, char *data, int32_t rows, void *pConn) {
@@ -622,10 +627,13 @@ static int32_t mnodeRetrieveDbs(SShowObj *pShow, char *data, int32_t rows, void
 
     cols = 0;
 
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    
+    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;  
     char* name = mnodeGetDbStr(pDb->name);
-    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, name, pShow->bytes[cols]);
+    if (name != NULL) {
+      STR_WITH_MAXSIZE_TO_VARSTR(pWrite, name, pShow->bytes[cols]);
+    } else {
+      STR_TO_VARSTR(pWrite, "NULL");
+    }
     cols++;
 
     pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
diff --git a/src/mnode/src/mnodeSdb.c b/src/mnode/src/mnodeSdb.c
index 42ded7ed067e0f81a0927a4954069dd73c5e16ff..4b2945152b3c0a30b088a5d2217d44f13406ad8e 100644
--- a/src/mnode/src/mnodeSdb.c
+++ b/src/mnode/src/mnodeSdb.c
@@ -406,7 +406,7 @@ void sdbDecRef(void *handle, void *pObj) {
   int32_t    refCount = atomic_sub_fetch_32(pRefCount, 1);
   sdbTrace("def ref of table:%s record:%p:%s:%d", pTable->tableName, pObj, sdbGetKeyStrFromObj(pTable, pObj), *pRefCount);
 
-  int8_t *updateEnd = pObj + pTable->refCountPos - 1;
+  int32_t *updateEnd = pObj + pTable->refCountPos - 4;
   if (refCount <= 0 && *updateEnd) {
     sdbTrace("table:%s, record:%p:%s:%d is destroyed", pTable->tableName, pObj, sdbGetKeyStrFromObj(pTable, pObj), *pRefCount);
     SSdbOper oper = {.pObj = pObj};
@@ -453,7 +453,7 @@ static int32_t sdbInsertHash(SSdbTable *pTable, SSdbOper *pOper) {
     keySize = strlen((char *)key);
   }
 
-  taosHashPut(pTable->iHandle, key, keySize, &pOper->pObj, sizeof(void **));
+  taosHashPut(pTable->iHandle, key, keySize, &pOper->pObj, sizeof(int64_t));
 
   sdbIncRef(pTable, pOper->pObj);
   atomic_add_fetch_32(&pTable->numOfRows, 1);
@@ -472,6 +472,14 @@ static int32_t sdbInsertHash(SSdbTable *pTable, SSdbOper *pOper) {
 }
 
 static int32_t sdbDeleteHash(SSdbTable *pTable, SSdbOper *pOper) {
+  int32_t *updateEnd = pOper->pObj + pTable->refCountPos - 4;
+  bool set = atomic_val_compare_exchange_32(updateEnd, 0, 1) == 0;
+  if (!set) {
+    sdbError("table:%s, failed to delete record:%s from hash, for it already removed", pTable->tableName,
+             sdbGetKeyStrFromObj(pTable, pOper->pObj));
+    return TSDB_CODE_MND_SDB_OBJ_NOT_THERE;
+  }
+
   (*pTable->deleteFp)(pOper);
   
   void *  key = sdbGetObjKey(pTable, pOper->pObj);
@@ -486,8 +494,6 @@ static int32_t sdbDeleteHash(SSdbTable *pTable, SSdbOper *pOper) {
   sdbDebug("table:%s, delete record:%s from hash, numOfRows:%" PRId64 ", msg:%p", pTable->tableName,
            sdbGetKeyStrFromObj(pTable, pOper->pObj), pTable->numOfRows, pOper->pMsg);
 
-  int8_t *updateEnd = pOper->pObj + pTable->refCountPos - 1;
-  *updateEnd = 1;
   sdbDecRef(pTable, pOper->pObj);
 
   return TSDB_CODE_SUCCESS;
@@ -654,8 +660,9 @@ bool sdbCheckRowDeleted(void *pTableInput, void *pRow) {
   SSdbTable *pTable = pTableInput;
   if (pTable == NULL) return false;
 
-  int8_t *updateEnd = pRow + pTable->refCountPos - 1;
-  return (*updateEnd == 1);
+  int32_t *updateEnd = pRow + pTable->refCountPos - 4;
+  return atomic_val_compare_exchange_32(updateEnd, 1, 1) == 1;
+  // return (*updateEnd == 1);
 }
 
 int32_t sdbDeleteRow(SSdbOper *pOper) {
diff --git a/src/mnode/src/mnodeShow.c b/src/mnode/src/mnodeShow.c
index e3d5b41be317272501bf84607f41adb50c43fbd6..1d85a8cacd92cc2b9f33c36828308edf764d4aef 100644
--- a/src/mnode/src/mnodeShow.c
+++ b/src/mnode/src/mnodeShow.c
@@ -236,7 +236,7 @@ static int32_t mnodeProcessHeartBeatMsg(SMnodeMsg *pMsg) {
   }
 
   SCMHeartBeatMsg *pHBMsg = pMsg->rpcMsg.pCont;
-  SRpcConnInfo connInfo;
+  SRpcConnInfo connInfo = {0};
   rpcGetConnInfo(pMsg->rpcMsg.handle, &connInfo);
     
   int32_t connId = htonl(pHBMsg->connId);
@@ -284,7 +284,7 @@ static int32_t mnodeProcessConnectMsg(SMnodeMsg *pMsg) {
   SCMConnectRsp *pConnectRsp = NULL;
   int32_t code = TSDB_CODE_SUCCESS;
 
-  SRpcConnInfo connInfo;
+  SRpcConnInfo connInfo = {0};
   if (rpcGetConnInfo(pMsg->rpcMsg.handle, &connInfo) != 0) {
     mError("thandle:%p is already released while process connect msg", pMsg->rpcMsg.handle);
     code = TSDB_CODE_MND_INVALID_CONNECTION;
diff --git a/src/mnode/src/mnodeTable.c b/src/mnode/src/mnodeTable.c
index 7478d7cd78712f0d4c131a3089aaeaaf93a76f8e..12ab58d9492bb4c65d7169e36c68e2707553c62f 100644
--- a/src/mnode/src/mnodeTable.c
+++ b/src/mnode/src/mnodeTable.c
@@ -72,7 +72,7 @@ static void    mnodeProcessCreateChildTableRsp(SRpcMsg *rpcMsg);
 static int32_t mnodeProcessDropTableMsg(SMnodeMsg *mnodeMsg);
 static int32_t mnodeProcessDropSuperTableMsg(SMnodeMsg *pMsg);
 static void    mnodeProcessDropSuperTableRsp(SRpcMsg *rpcMsg);
-static int32_t mnodeProcessDropChildTableMsg(SMnodeMsg *pMsg, bool needReturn);
+static int32_t mnodeProcessDropChildTableMsg(SMnodeMsg *pMsg);
 static void    mnodeProcessDropChildTableRsp(SRpcMsg *rpcMsg);
 
 static int32_t mnodeProcessSuperTableVgroupMsg(SMnodeMsg *mnodeMsg);
@@ -759,7 +759,7 @@ static int32_t mnodeProcessDropTableMsg(SMnodeMsg *pMsg) {
     SChildTableObj *pCTable = (SChildTableObj *)pMsg->pTable;
     mInfo("app:%p:%p, table:%s, start to drop ctable, vgId:%d sid:%d uid:%" PRIu64, pMsg->rpcMsg.ahandle, pMsg,
           pDrop->tableId, pCTable->vgId, pCTable->sid, pCTable->uid);
-    return mnodeProcessDropChildTableMsg(pMsg, true);
+    return mnodeProcessDropChildTableMsg(pMsg);
   }
 }
 
@@ -882,7 +882,7 @@ static int32_t mnodeProcessCreateSuperTableMsg(SMnodeMsg *pMsg) {
 static int32_t mnodeDropSuperTableCb(SMnodeMsg *pMsg, int32_t code) {
   SSuperTableObj *pTable = (SSuperTableObj *)pMsg->pTable;
   if (code != TSDB_CODE_SUCCESS) {
-    mError("app:%p:%p, table:%s, failed to drop, sdb error", pMsg->rpcMsg.ahandle, pMsg, pTable->info.tableId);
+    mError("app:%p:%p, stable:%s, failed to drop, sdb error", pMsg->rpcMsg.ahandle, pMsg, pTable->info.tableId);
   } else {
     mLInfo("app:%p:%p, stable:%s, is dropped from sdb", pMsg->rpcMsg.ahandle, pMsg, pTable->info.tableId);
   }
@@ -1765,18 +1765,13 @@ static int32_t mnodeProcessCreateChildTableMsg(SMnodeMsg *pMsg) {
   }
 }
 
-static int32_t mnodeProcessDropChildTableMsg(SMnodeMsg *pMsg, bool needReturn) {
+static int32_t mnodeSendDropChildTableMsg(SMnodeMsg *pMsg, bool needReturn) {
   SChildTableObj *pTable = (SChildTableObj *)pMsg->pTable;
-  if (pMsg->pVgroup == NULL) pMsg->pVgroup = mnodeGetVgroup(pTable->vgId);
-  if (pMsg->pVgroup == NULL) {
-    mError("app:%p:%p, table:%s, failed to drop ctable, vgroup not exist", pMsg->rpcMsg.ahandle, pMsg,
-           pTable->info.tableId);
-    return TSDB_CODE_MND_APP_ERROR;
-  }
+  mLInfo("app:%p:%p, ctable:%s, is dropped from sdb", pMsg->rpcMsg.ahandle, pMsg, pTable->info.tableId);
 
   SMDDropTableMsg *pDrop = rpcMallocCont(sizeof(SMDDropTableMsg));
   if (pDrop == NULL) {
-    mError("app:%p:%p, table:%s, failed to drop ctable, no enough memory", pMsg->rpcMsg.ahandle, pMsg,
+    mError("app:%p:%p, ctable:%s, failed to drop ctable, no enough memory", pMsg->rpcMsg.ahandle, pMsg,
            pTable->info.tableId);
     return TSDB_CODE_MND_OUT_OF_MEMORY;
   }
@@ -1789,7 +1784,7 @@ static int32_t mnodeProcessDropChildTableMsg(SMnodeMsg *pMsg, bool needReturn) {
 
   SRpcEpSet epSet = mnodeGetEpSetFromVgroup(pMsg->pVgroup);
 
-  mInfo("app:%p:%p, table:%s, send drop ctable msg, vgId:%d sid:%d uid:%" PRIu64, pMsg->rpcMsg.ahandle, pMsg,
+  mInfo("app:%p:%p, ctable:%s, send drop ctable msg, vgId:%d sid:%d uid:%" PRIu64, pMsg->rpcMsg.ahandle, pMsg,
         pDrop->tableId, pTable->vgId, pTable->sid, pTable->uid);
 
   SRpcMsg rpcMsg = {
@@ -1807,6 +1802,40 @@ static int32_t mnodeProcessDropChildTableMsg(SMnodeMsg *pMsg, bool needReturn) {
   return TSDB_CODE_MND_ACTION_IN_PROGRESS;
 }
 
+static int32_t mnodeDropChildTableCb(SMnodeMsg *pMsg, int32_t code) {
+  if (code != TSDB_CODE_SUCCESS) {
+    SChildTableObj *pTable = (SChildTableObj *)pMsg->pTable;
+    mError("app:%p:%p, ctable:%s, failed to drop, sdb error", pMsg->rpcMsg.ahandle, pMsg, pTable->info.tableId);
+    return code;
+  } 
+
+  return mnodeSendDropChildTableMsg(pMsg, true);
+}
+
+static int32_t mnodeProcessDropChildTableMsg(SMnodeMsg *pMsg) {
+  SChildTableObj *pTable = (SChildTableObj *)pMsg->pTable;
+  if (pMsg->pVgroup == NULL) pMsg->pVgroup = mnodeGetVgroup(pTable->vgId);
+  if (pMsg->pVgroup == NULL) {
+    mError("app:%p:%p, table:%s, failed to drop ctable, vgroup not exist", pMsg->rpcMsg.ahandle, pMsg,
+           pTable->info.tableId);
+    return TSDB_CODE_MND_APP_ERROR;
+  }
+
+  SSdbOper oper = {
+    .type  = SDB_OPER_GLOBAL,
+    .table = tsChildTableSdb,
+    .pObj  = pTable,
+    .pMsg  = pMsg,
+    .cb    = mnodeDropChildTableCb
+  };
+
+  int32_t code = sdbDeleteRow(&oper);
+  if (code == TSDB_CODE_SUCCESS) {
+    return TSDB_CODE_MND_ACTION_IN_PROGRESS;
+  }
+  return code;
+}
+
 static int32_t mnodeFindNormalTableColumnIndex(SChildTableObj *pTable, char *colName) {
   SSchema *schema = (SSchema *) pTable->schema;
   for (int32_t col = 0; col < pTable->numOfColumns; col++) {
@@ -2220,19 +2249,6 @@ static void mnodeProcessDropChildTableRsp(SRpcMsg *rpcMsg) {
     return;
   }
 
-  SSdbOper oper = {
-    .type = SDB_OPER_GLOBAL,
-    .table = tsChildTableSdb,
-    .pObj = pTable
-  };
-
-  int32_t code = sdbDeleteRow(&oper);
-  if (code != TSDB_CODE_SUCCESS) {
-    mError("app:%p:%p, table:%s, update ctables sdb error", mnodeMsg->rpcMsg.ahandle, mnodeMsg, pTable->info.tableId);
-    dnodeSendRpcMnodeWriteRsp(mnodeMsg, TSDB_CODE_MND_SDB_ERROR);
-    return;
-  }
-
   if (mnodeMsg->pVgroup->numOfTables <= 0) {
     mInfo("app:%p:%p, vgId:%d, all tables is dropped, drop vgroup", mnodeMsg->rpcMsg.ahandle, mnodeMsg,
            mnodeMsg->pVgroup->vgId);
@@ -2259,7 +2275,7 @@ static void mnodeProcessCreateChildTableRsp(SRpcMsg *rpcMsg) {
   if (sdbCheckRowDeleted(tsChildTableSdb, pTable)) {
     mDebug("app:%p:%p, table:%s, create table rsp received, but a deleting opertion incoming, vgId:%d sid:%d uid:%" PRIu64,
            mnodeMsg->rpcMsg.ahandle, mnodeMsg, pTable->info.tableId, pTable->vgId, pTable->sid, pTable->uid);
-    mnodeProcessDropChildTableMsg(mnodeMsg, false);
+    mnodeSendDropChildTableMsg(mnodeMsg, false);
     rpcMsg->code = TSDB_CODE_SUCCESS;
   }
 
diff --git a/src/mnode/src/mnodeUser.c b/src/mnode/src/mnodeUser.c
index 84f5d6aa58403ca887c9a6be6d52fad5ad63be1d..8c783eebaf64fe377b9756e26196573c8fdfcaca 100644
--- a/src/mnode/src/mnodeUser.c
+++ b/src/mnode/src/mnodeUser.c
@@ -358,7 +358,7 @@ static int32_t mnodeRetrieveUsers(SShowObj *pShow, char *data, int32_t rows, voi
 }
 
 SUserObj *mnodeGetUserFromConn(void *pConn) {
-  SRpcConnInfo connInfo;
+  SRpcConnInfo connInfo = {0};
   if (rpcGetConnInfo(pConn, &connInfo) == 0) {
     return mnodeGetUser(connInfo.user);
   } else {
diff --git a/src/mnode/src/mnodeVgroup.c b/src/mnode/src/mnodeVgroup.c
index 1de591df7cd627e1b6b33a28d5174024e1d55875..46255a6c8f96be2b2bd3ab642e54bd0013b12958 100644
--- a/src/mnode/src/mnodeVgroup.c
+++ b/src/mnode/src/mnodeVgroup.c
@@ -434,15 +434,22 @@ int32_t mnodeGetAvailableVgroup(SMnodeMsg *pMsg, SVgObj **ppVgroup, int32_t *pSi
   }
 
   if (pDb->numOfVgroups < maxVgroupsPerDb) {
-    mDebug("app:%p:%p, db:%s, try to create a new vgroup, numOfVgroups:%d maxVgroupsPerDb:%d", pMsg->rpcMsg.ahandle, pMsg,
-           pDb->name, pDb->numOfVgroups, maxVgroupsPerDb);
+    mDebug("app:%p:%p, db:%s, try to create a new vgroup, numOfVgroups:%d maxVgroupsPerDb:%d", pMsg->rpcMsg.ahandle,
+           pMsg, pDb->name, pDb->numOfVgroups, maxVgroupsPerDb);
     pthread_mutex_unlock(&pDb->mutex);
     int32_t code = mnodeCreateVgroup(pMsg);
-    if (code == TSDB_CODE_MND_ACTION_IN_PROGRESS) return code;
+    if (code == TSDB_CODE_MND_ACTION_IN_PROGRESS) {
+      return code;
+    } else {
+      pthread_mutex_lock(&pDb->mutex);
+    }
   }
 
   SVgObj *pVgroup = pDb->vgList[0];
-  if (pVgroup == NULL) return TSDB_CODE_MND_NO_ENOUGH_DNODES;
+  if (pVgroup == NULL) {
+    pthread_mutex_unlock(&pDb->mutex);
+    return TSDB_CODE_MND_NO_ENOUGH_DNODES;
+  }
 
   int32_t code = mnodeAllocVgroupIdPool(pVgroup);
   if (code != TSDB_CODE_SUCCESS) {
@@ -483,7 +490,7 @@ static int32_t mnodeCreateVgroupCb(SMnodeMsg *pMsg, int32_t code) {
   } else {
     pVgroup->status = TAOS_VG_STATUS_READY;
     SSdbOper desc = {.type = SDB_OPER_GLOBAL, .pObj = pVgroup, .table = tsVgroupSdb};
-    sdbUpdateRow(&desc);
+    (void)sdbUpdateRow(&desc);
   }
 
   mInfo("app:%p:%p, vgId:%d, is created in mnode, db:%s replica:%d", pMsg->rpcMsg.ahandle, pMsg, pVgroup->vgId,
diff --git a/src/plugins/http/src/gcJson.c b/src/plugins/http/src/gcJson.c
index 544a11b5fc925c8c948e26f182e5d1cbd8b1e4c3..94d53db6ef0200265aa67710794c60f1fec0cfac 100644
--- a/src/plugins/http/src/gcJson.c
+++ b/src/plugins/http/src/gcJson.c
@@ -121,6 +121,10 @@ bool gcBuildQueryJson(HttpContext *pContext, HttpSqlCmd *cmd, TAOS_RES *result,
 
   for (int k = 0; k < numOfRows; ++k) {
     TAOS_ROW row = taos_fetch_row(result);
+    if (row == NULL) {
+      cmd->numOfRows--;
+      continue;
+    }
     int32_t* length = taos_fetch_lengths(result);
 
     // for group by
diff --git a/src/plugins/http/src/httpContext.c b/src/plugins/http/src/httpContext.c
index cefcca78215da2267001099aa7f728527f481ffa..225977abae698ccfeb12c36562d5588a3f166027 100644
--- a/src/plugins/http/src/httpContext.c
+++ b/src/plugins/http/src/httpContext.c
@@ -108,7 +108,7 @@ HttpContext *httpCreateContext(int32_t fd) {
   pContext->lastAccessTime = taosGetTimestampSec();
   pContext->state = HTTP_CONTEXT_STATE_READY;
 
-  HttpContext **ppContext = taosCachePut(tsHttpServer.contextCache, &pContext, sizeof(void *), &pContext, sizeof(void *), 3);
+  HttpContext **ppContext = taosCachePut(tsHttpServer.contextCache, &pContext, sizeof(int64_t), &pContext, sizeof(int64_t), 3);
   pContext->ppContext = ppContext;
   httpDebug("context:%p, fd:%d, is created, data:%p", pContext, fd, ppContext);
 
diff --git a/src/plugins/http/src/restJson.c b/src/plugins/http/src/restJson.c
index 53b0248149d3f72a35d99dc9757fcb36c085a857..7a73f6559f21427d04d37289338d73ec64306dc0 100644
--- a/src/plugins/http/src/restJson.c
+++ b/src/plugins/http/src/restJson.c
@@ -94,6 +94,10 @@ bool restBuildSqlJson(HttpContext *pContext, HttpSqlCmd *cmd, TAOS_RES *result,
 
   for (int k = 0; k < numOfRows; ++k) {
     TAOS_ROW row = taos_fetch_row(result);
+    if (row == NULL) {
+      cmd->numOfRows--;
+      continue;
+    }
     int32_t* length = taos_fetch_lengths(result);
 
     // data row array begin
diff --git a/src/plugins/mqtt/src/mqttSystem.c b/src/plugins/mqtt/src/mqttSystem.c
index 2687106124497607a50c8b1435497cd2c467722a..0259ea23eb66239b1e7fbfcb6d0243a16dabb32f 100644
--- a/src/plugins/mqtt/src/mqttSystem.c
+++ b/src/plugins/mqtt/src/mqttSystem.c
@@ -64,7 +64,7 @@ int32_t mqttInitSystem() {
   }
 
   char* _begin_hostname = strstr(url, recntStatus.hostname);
-  if (strstr(_begin_hostname, ":") != NULL) {
+  if (_begin_hostname != NULL && strstr(_begin_hostname, ":") != NULL) {
     recntStatus.port = strbetween(_begin_hostname, ":", "/");
   } else {
     recntStatus.port = strbetween("'1883'", "'", "'");