diff --git a/src/client/src/tscSecondaryMerge.c b/src/client/src/tscSecondaryMerge.c
index 84f14abf4c68c8f561abfa2b918db7ef79ba7c30..dbf17b56c5cb7893a4272d141902bf1559349ea2 100644
--- a/src/client/src/tscSecondaryMerge.c
+++ b/src/client/src/tscSecondaryMerge.c
@@ -140,7 +140,13 @@ void tscCreateLocalReducer(tExtMemBuffer **pMemBuffer, int32_t numOfBuffer, tOrd
   // offset of cmd in SSqlObj structure
   char *pSqlObjAddr = (char *)pCmd - offsetof(SSqlObj, cmd);
 
-  if (pMemBuffer == NULL || pDesc->pColumnModel == NULL) {
+  if (pMemBuffer == NULL) {
+    tscError("%p pMemBuffer", pMemBuffer);
+    pRes->code = TSDB_CODE_APP_ERROR;
+    return;
+  }
+ 
+  if (pDesc->pColumnModel == NULL) {
     tscLocalReducerEnvDestroy(pMemBuffer, pDesc, finalmodel, numOfBuffer);
 
     tscError("%p no local buffer or intermediate result format model", pSqlObjAddr);
diff --git a/src/client/src/tscServer.c b/src/client/src/tscServer.c
index 9b44bea82d1c9927b9ef2cf1331af5bf7267d7f9..7874d0e8167aa1b3d824a6860316ceab4e5c567d 100644
--- a/src/client/src/tscServer.c
+++ b/src/client/src/tscServer.c
@@ -228,7 +228,11 @@ int tscSendMsgToServer(SSqlObj *pSql) {
 
 void tscProcessMsgFromServer(SRpcMsg *rpcMsg) {
   SSqlObj *pSql = (SSqlObj *)rpcMsg->handle;
-  if (pSql == NULL || pSql->signature != pSql) {
+  if (pSql == NULL) {
+    tscError("%p sql is already released", pSql->signature);
+    return;
+  }
+  if (pSql->signature != pSql) {
     tscError("%p sql is already released, signature:%p", pSql, pSql->signature);
     return;
   }
@@ -310,7 +314,7 @@ void tscProcessMsgFromServer(SRpcMsg *rpcMsg) {
     pRes->rspType = rpcMsg->msgType;
     pRes->rspLen  = rpcMsg->contLen;
 
-    if (pRes->rspLen > 0) {
+    if (pRes->rspLen > 0 && rpcMsg->pCont) {
       char *tmp = (char *)realloc(pRes->pRsp, pRes->rspLen);
       if (tmp == NULL) {
         pRes->code = TSDB_CODE_CLI_OUT_OF_MEMORY;
diff --git a/src/client/src/tscStream.c b/src/client/src/tscStream.c
index d69068172937692ac95dd6ca64717b00e236321b..5f5af09cf8aa84712c166e12c508fbf1a3b20dc3 100644
--- a/src/client/src/tscStream.c
+++ b/src/client/src/tscStream.c
@@ -172,17 +172,17 @@ static void tscSetTimestampForRes(SSqlStream *pStream, SSqlObj *pSql) {
 static void tscProcessStreamRetrieveResult(void *param, TAOS_RES *res, int numOfRows) {
   SSqlStream *    pStream = (SSqlStream *)param;
   SSqlObj *       pSql = (SSqlObj *)res;
-  STableMetaInfo *pTableMetaInfo = tscGetTableMetaInfoFromCmd(&pSql->cmd, 0, 0);
 
   if (pSql == NULL || numOfRows < 0) {
     int64_t retryDelayTime = tscGetRetryDelayTime(pStream->slidingTime, pStream->precision);
     tscError("%p stream:%p, retrieve data failed, code:%d, retry in %" PRId64 "ms", pSql, pStream, numOfRows, retryDelayTime);
-    tscClearTableMetaInfo(pTableMetaInfo, true);
   
     tscSetRetryTimer(pStream, pStream->pSql, retryDelayTime);
     return;
   }
 
+  STableMetaInfo *pTableMetaInfo = tscGetTableMetaInfoFromCmd(&pSql->cmd, 0, 0);
+
   if (numOfRows > 0) { // when reaching here the first execution of stream computing is successful.
     pStream->numOfRes += numOfRows;
     SQueryInfo* pQueryInfo = tscGetQueryInfoDetail(&pSql->cmd, 0);
diff --git a/src/client/src/tscUtil.c b/src/client/src/tscUtil.c
index c0cfa4d3af3fc142bb15afa3d84bff8b99ba35ad..506fa1a60560baf5da1e5f401a2ad0798651fcc3 100644
--- a/src/client/src/tscUtil.c
+++ b/src/client/src/tscUtil.c
@@ -757,7 +757,9 @@ void tscCloseTscObj(STscObj* pObj) {
   taosTmrStopA(&(pObj->pTimer));
   tscFreeSqlObj(pSql);
 
-  sem_destroy(&pSql->rspSem);
+  if (pSql) {
+    sem_destroy(&pSql->rspSem);
+  }
   rpcClose(pObj->pMgmtConn);
   
   pthread_mutex_destroy(&pObj->mutex);
diff --git a/src/dnode/src/dnodeMain.c b/src/dnode/src/dnodeMain.c
index 6aa42f05c700d5bd21b160da344a3939e0545918..940b884927719986009d6934802e2972cab49399 100644
--- a/src/dnode/src/dnodeMain.c
+++ b/src/dnode/src/dnodeMain.c
@@ -213,6 +213,7 @@ static void dnodeCheckDataDirOpenned(char *dir) {
   int32_t ret = flock(fd, LOCK_EX | LOCK_NB);
   if (ret != 0) {
     dError("failed to lock file:%s ret:%d, database may be running, quit", filepath, ret);
+    close(fd);
     exit(0);
   }
 }
diff --git a/src/kit/shell/src/shellImport.c b/src/kit/shell/src/shellImport.c
index 256b251075b564727f886ea0d4da220329806a37..e5c50bb74ef3dea925729056143742fd6101ce3f 100644
--- a/src/kit/shell/src/shellImport.c
+++ b/src/kit/shell/src/shellImport.c
@@ -142,6 +142,7 @@ static void shellSourceFile(TAOS *con, char *fptr) {
 
   if (wordexp(fptr, &full_path, 0) != 0) {
     fprintf(stderr, "ERROR: illegal file name\n");
+    free(cmd);
     return;
   }
 
diff --git a/src/kit/shell/src/shellLinux.c b/src/kit/shell/src/shellLinux.c
index d3453cda3639654dd4f92f4afd289f72825de0f2..22ffa78c8138dcf14ed384c88fec27e205dc6b47 100644
--- a/src/kit/shell/src/shellLinux.c
+++ b/src/kit/shell/src/shellLinux.c
@@ -62,7 +62,13 @@ static error_t parse_opt(int key, char *arg, struct argp_state *state) {
       if (arg) arguments->password = arg;
       break;
     case 'P':
-      tsMnodeShellPort = atoi(arg);
+      if (arg) {
+        tsMnodeShellPort = atoi(arg);
+      } else {
+        fprintf(stderr, "Invalid port\n");
+        return -1;
+      }
+
       break;
     case 't':
       arguments->timezone = arg;
@@ -101,7 +107,12 @@ static error_t parse_opt(int key, char *arg, struct argp_state *state) {
       wordfree(&full_path);
       break;
     case 'T':
-      arguments->threadNum = atoi(arg);
+      if (arg) {
+        arguments->threadNum = atoi(arg);
+      } else {
+        fprintf(stderr, "Invalid number of threads\n");
+        return -1;
+      }
       break;
     case 'd':
       arguments->database = arg;
diff --git a/src/kit/taosdemo/taosdemo.c b/src/kit/taosdemo/taosdemo.c
index 24855ab8b51a87aed91ac10e8278941fe60bfee1..937c8d177dc73138e626f83b18657cbb8eb485a2 100644
--- a/src/kit/taosdemo/taosdemo.c
+++ b/src/kit/taosdemo/taosdemo.c
@@ -340,6 +340,9 @@ int main(int argc, char *argv[]) {
   int count_data_type = 0;
   char dataString[512];
   bool do_aggreFunc = true;
+
+  memset(dataString, 0, 512);
+
   if (strcasecmp(data_type[0], "BINARY") == 0 || strcasecmp(data_type[0], "BOOL") == 0) {
     do_aggreFunc = false;
   }
diff --git a/src/kit/taosdump/taosdump.c b/src/kit/taosdump/taosdump.c
index 2e64c9bcccba8c749de3a73e6480bf056b067e56..ed98a9b92c517b4387b8144cf5a8082e91384ad2 100644
--- a/src/kit/taosdump/taosdump.c
+++ b/src/kit/taosdump/taosdump.c
@@ -383,14 +383,13 @@ int taosGetTableRecordInfo(char *table, STableRecordInfo *pTableRecordInfo) {
 
   TAOS_FIELD *fields = taos_fetch_fields(result);
 
-  while ((row = taos_fetch_row(result)) != NULL) {
+  if ((row = taos_fetch_row(result)) != NULL) {
     isSet = true;
     pTableRecordInfo->isMetric = false;
     strncpy(pTableRecordInfo->tableRecord.name, (char *)row[TSDB_SHOW_TABLES_NAME_INDEX],
             fields[TSDB_SHOW_TABLES_NAME_INDEX].bytes);
     strncpy(pTableRecordInfo->tableRecord.metric, (char *)row[TSDB_SHOW_TABLES_METRIC_INDEX],
             fields[TSDB_SHOW_TABLES_METRIC_INDEX].bytes);
-    break;
   }
 
   taos_free_result(result);
@@ -410,11 +409,10 @@ int taosGetTableRecordInfo(char *table, STableRecordInfo *pTableRecordInfo) {
     return -1;
   }
 
-  while ((row = taos_fetch_row(result)) != NULL) {
+  if ((row = taos_fetch_row(result)) != NULL) {
     isSet = true;
     pTableRecordInfo->isMetric = true;
     strcpy(pTableRecordInfo->tableRecord.metric, table);
-    break;
   }
 
   taos_free_result(result);
diff --git a/src/mnode/src/mgmtShell.c b/src/mnode/src/mgmtShell.c
index 193521b0260c42213f3d07578fa129a33c206f65..05cacbb95c58debddc9d225100bf98fe6411e06c 100644
--- a/src/mnode/src/mgmtShell.c
+++ b/src/mnode/src/mgmtShell.c
@@ -149,7 +149,9 @@ void mgmtDealyedAddToShellQueue(SQueuedMsg *queuedMsg) {
 }
 
 static void mgmtProcessMsgFromShell(SRpcMsg *rpcMsg) {
-  if (rpcMsg == NULL || rpcMsg->pCont == NULL) {
+  assert(rpcMsg);
+
+  if (rpcMsg->pCont == NULL) {
     mgmtSendSimpleResp(rpcMsg->handle, TSDB_CODE_INVALID_MSG_LEN);
     return;
   }
diff --git a/src/mnode/src/mgmtVgroup.c b/src/mnode/src/mgmtVgroup.c
index 839dce5c38a65528e1ea3c0f8c691738476bce45..b3260850ad03e8d7c111c96a9526f013988df0ee 100644
--- a/src/mnode/src/mgmtVgroup.c
+++ b/src/mnode/src/mgmtVgroup.c
@@ -158,7 +158,11 @@ static int32_t mgmtVgroupActionUpdate(SSdbOper *pOper) {
   }
 
   mgmtDecVgroupRef(pVgroup);
-  mTrace("vgId:%d, is updated, tables:%d numOfVnode:%d", pVgroup->vgId, pDb->cfg.maxTables, pVgroup->numOfVnodes);
+
+  mTrace("vgId:%d, is updated, numOfVnode:%d", pVgroup->vgId, pVgroup->numOfVnodes);
+  if (pDb) {
+    mTrace("tables:%d", pDb->cfg.maxTables);
+  }
   return TSDB_CODE_SUCCESS;
 }
 
diff --git a/src/query/src/qparserImpl.c b/src/query/src/qparserImpl.c
index 075dbc9d14b2fda785e3730275b5e1803f1ea570..7b3a76c9d223ab12936ad348433dcfc0055e27ee 100644
--- a/src/query/src/qparserImpl.c
+++ b/src/query/src/qparserImpl.c
@@ -675,7 +675,7 @@ void SQLInfoDestroy(SSqlInfo *pInfo) {
       free(pInfo->pDCLInfo->a);
     }
 
-    if (pInfo->type == TSDB_SQL_CREATE_DB) {
+    if (pInfo->pDCLInfo != NULL && pInfo->type == TSDB_SQL_CREATE_DB) {
       tVariantListDestroy(pInfo->pDCLInfo->dbOpt.keep);
     }
 
@@ -899,4 +899,4 @@ void setDefaultCreateDbOption(SCreateDBInfo *pDBInfo) {
   pDBInfo->keep = NULL;
 
   memset(&pDBInfo->precision, 0, sizeof(SSQLToken));
-}
\ No newline at end of file
+}
diff --git a/src/query/src/qtsbuf.c b/src/query/src/qtsbuf.c
index 062a8038b2699a7be77e7eca3290fedfe9321785..1d5c4f2d9df71d9fc1133e424efeabbc40215043 100644
--- a/src/query/src/qtsbuf.c
+++ b/src/query/src/qtsbuf.c
@@ -636,12 +636,16 @@ void tsBufResetPos(STSBuf* pTSBuf) {
 
 STSElem tsBufGetElem(STSBuf* pTSBuf) {
   STSElem    elem1 = {.vnode = -1};
-  STSCursor* pCur = &pTSBuf->cur;
   
-  if (pTSBuf == NULL || pCur->vnodeIndex < 0) {
+  if (pTSBuf == NULL) {
     return elem1;
   }
   
+  STSCursor* pCur = &pTSBuf->cur;
+  if (pCur != NULL && pCur->vnodeIndex < 0) {
+    return elem1;
+  }
+
   STSBlock* pBlock = &pTSBuf->block;
   
   elem1.vnode = pTSBuf->pData[pCur->vnodeIndex].info.vnode;
@@ -920,4 +924,4 @@ static STSBuf* allocResForTSBuf(STSBuf* pTSBuf) {
   
   pTSBuf->fileSize += getDataStartOffset();
   return pTSBuf;
-}
\ No newline at end of file
+}
diff --git a/src/query/src/queryUtil.c b/src/query/src/queryUtil.c
index b4d8911284723d6b40fada3e17e1edefd53d549b..9da02f9f0f9d97c5087027309bde844c09589ecd 100644
--- a/src/query/src/queryUtil.c
+++ b/src/query/src/queryUtil.c
@@ -62,7 +62,10 @@ void destroyTimeWindowRes(SWindowResult *pWindowRes, int32_t nOutputCols) {
 }
 
 void cleanupTimeWindowInfo(SWindowResInfo *pWindowResInfo, int32_t numOfCols) {
-  if (pWindowResInfo == NULL || pWindowResInfo->capacity == 0) {
+  if (pWindowResInfo == NULL) {
+    return;
+  }
+  if (pWindowResInfo->capacity == 0) {
     assert(pWindowResInfo->hashList == NULL && pWindowResInfo->pResult == NULL);
     return;
   }
diff --git a/src/tsdb/src/tsdbRead.c b/src/tsdb/src/tsdbRead.c
index bc9220dbc72b197785b5fa227340def9e1839dbb..46480b2b9d06070a06c878c71f17c9fff7edd3db 100644
--- a/src/tsdb/src/tsdbRead.c
+++ b/src/tsdb/src/tsdbRead.c
@@ -216,7 +216,7 @@ static bool hasMoreDataInCache(STsdbQueryHandle* pHandle) {
     return false;
   }
   
-  if (pCheckInfo->iter == NULL) {
+  if (pCheckInfo->iter == NULL && pTable->mem) {
     pCheckInfo->iter = tSkipListCreateIterFromVal(pTable->mem->pData, (const char*) &pCheckInfo->lastKey,
         TSDB_DATA_TYPE_TIMESTAMP, pHandle->order);