diff --git a/src/client/src/tscJoinProcess.c b/src/client/src/tscJoinProcess.c
index 24d8ad902acb683f3b3ae05c10a5ff92181695df..17ea5cf8862f3fdb42f95cc80b84acf9394d26ae 100644
--- a/src/client/src/tscJoinProcess.c
+++ b/src/client/src/tscJoinProcess.c
@@ -1203,16 +1203,20 @@ bool tsBufNextPos(STSBuf* pTSBuf) {
   if (pCur->vnodeIndex == -1) {
     if (pCur->order == TSQL_SO_ASC) {
       tsBufGetBlock(pTSBuf, 0, 0);
-      // list is empty
-      if (pTSBuf->block.numOfElem == 0) {
+      
+      if (pTSBuf->block.numOfElem == 0) { // the whole list is empty, return
         tsBufResetPos(pTSBuf);
         return false;
       } else {
         return true;
       }
-    } else {
+      
+    } else { // get the last timestamp record in the last block of the last vnode
+      assert(pTSBuf->numOfVnodes > 0);
+      
       int32_t vnodeIndex = pTSBuf->numOfVnodes - 1;
-
+      pCur->vnodeIndex = vnodeIndex;
+      
       int32_t            vnodeId = pTSBuf->pData[pCur->vnodeIndex].info.vnode;
       STSVnodeBlockInfo* pBlockInfo = tsBufGetVnodeBlockInfo(pTSBuf, vnodeId);
       int32_t            blockIndex = pBlockInfo->numOfBlocks - 1;
diff --git a/src/client/src/tscParseInsert.c b/src/client/src/tscParseInsert.c
index 11bd33f17226bbf026f1296f4633ff3500b840f0..58cfcda17e27e42aae22c0f7a65658e6ce279476 100644
--- a/src/client/src/tscParseInsert.c
+++ b/src/client/src/tscParseInsert.c
@@ -155,7 +155,8 @@ int32_t tsParseOneColumnData(SSchema *pSchema, SSQLToken *pToken, char *payload,
   int64_t iv;
   int32_t numType;
   char *  endptr = NULL;
-
+  errno = 0;   // clear the previous existed error information
+  
   switch (pSchema->type) {
     case TSDB_DATA_TYPE_BOOL: {  // bool
       if ((pToken->type == TK_BOOL || pToken->type == TK_STRING) && (pToken->n != 0)) {
diff --git a/src/system/detail/src/vnodeQueryImpl.c b/src/system/detail/src/vnodeQueryImpl.c
index db0ec24395cbb15fd2bf619e6fe509a4a1b3652d..2d6332b05b0f282cb25ff2c88b3c2484e32e2c73 100644
--- a/src/system/detail/src/vnodeQueryImpl.c
+++ b/src/system/detail/src/vnodeQueryImpl.c
@@ -1395,7 +1395,7 @@ static int32_t doTSJoinFilter(SQueryRuntimeEnv *pRuntimeEnv, int32_t offset) {
 
   TSKEY key = *(TSKEY *)(pCtx[0].aInputElemBuf + TSDB_KEYSIZE * offset);
 
-#if 1
+#if defined(_DEBUG_VIEW)
   printf("elem in comp ts file:%lld, key:%lld, tag:%d, id:%s, query order:%d, ts order:%d, traverse:%d, index:%d\n",
          elem.ts, key, elem.tag, pRuntimeEnv->pMeterObj->meterId, pQuery->order.order, pRuntimeEnv->pTSBuf->tsOrder,
          pRuntimeEnv->pTSBuf->cur.order, pRuntimeEnv->pTSBuf->cur.tsIndex);
@@ -2919,6 +2919,7 @@ static int file_order_comparator(const void *p1, const void *p2) {
 
 /**
  * open a data files and header file for metric meta query
+ *
  * @param pQInfo
  * @param pVnodeFiles
  * @param fid
@@ -2929,8 +2930,6 @@ static int file_order_comparator(const void *p1, const void *p2) {
  */
 static int32_t vnodeOpenVnodeDBFiles(SQInfo *pQInfo, SQueryFileInfo *pVnodeFiles, int32_t fid, int32_t vnodeId,
                                      char *fileName, char *prefix) {
-  //  __off_t size = 0;
-
   pVnodeFiles->fileID = fid;
   pVnodeFiles->defaultMappingSize = DEFAULT_DATA_FILE_MMAP_WINDOW_SIZE;
 
diff --git a/src/system/detail/src/vnodeShell.c b/src/system/detail/src/vnodeShell.c
index 1937a2f3ef8c16c56b05cf46f0419b50e940f855..6b29d8aaba9432ddfade43400c6ee0f221a69f63 100644
--- a/src/system/detail/src/vnodeShell.c
+++ b/src/system/detail/src/vnodeShell.c
@@ -569,7 +569,6 @@ int vnodeProcessShellSubmitRequest(char *pMsg, int msgLen, SShellObj *pObj) {
     int sversion = htonl(pBlocks->sversion);
 
     if (pSubmit->import) {
-      dTrace("start to import data");
       code = vnodeImportPoints(pMeterObj, (char *) &(pBlocks->numOfRows), subMsgLen, TSDB_DATA_SOURCE_SHELL, pObj,
                                sversion, &numOfPoints, now);
     } else {