diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index 2b325afa7cb52c94404f2b2b4b49a4390c216d8c..22e91bd658d5769e80163dea3388e567294ae6c5 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -4487,10 +4487,12 @@ int32_t setAlterTableInfo(SSqlObj* pSql, struct SSqlInfo* pInfo) {
 
     SUpdateTableTagValMsg* pUpdateMsg = (SUpdateTableTagValMsg*) pCmd->payload;
     pUpdateMsg->head.vgId = htonl(pTableMeta->vgroupInfo.vgId);
-    pUpdateMsg->tid = htonl(pTableMeta->sid);
-    pUpdateMsg->uid = htobe64(pTableMeta->uid);
-    pUpdateMsg->colId = htons(pTagsSchema->colId);
-    pUpdateMsg->tversion = htons(pTableMeta->tversion);
+    pUpdateMsg->tid       = htonl(pTableMeta->sid);
+    pUpdateMsg->uid       = htobe64(pTableMeta->uid);
+    pUpdateMsg->colId     = htons(pTagsSchema->colId);
+    pUpdateMsg->type      = htons(pTagsSchema->type);
+    pUpdateMsg->bytes     = htons(pTagsSchema->bytes);
+    pUpdateMsg->tversion  = htons(pTableMeta->tversion);
     pUpdateMsg->numOfTags = htons(numOfTags);
     pUpdateMsg->schemaLen = htonl(schemaLen);
 
diff --git a/src/inc/taosmsg.h b/src/inc/taosmsg.h
index 6155f08e76646ff887a51be60a0bfa500a6f873c..184979797026d45e627f8d39716b8d3827c83ec7 100644
--- a/src/inc/taosmsg.h
+++ b/src/inc/taosmsg.h
@@ -285,6 +285,8 @@ typedef struct {
   int32_t   tid;
   int16_t   tversion;
   int16_t   colId;
+  int16_t   type;
+  int16_t   bytes;
   int32_t   tagValLen;
   int16_t   numOfTags;
   int32_t   schemaLen;
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 849453527eddd76f2a78ed1ec5d64580180a3cdb..7fe59fc443f800f30f6c18b149c44505955e33e1 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -1099,7 +1099,6 @@ static bool functionNeedToExecute(SQueryRuntimeEnv *pRuntimeEnv, SQLFunctionCtx
   // todo add comments
   if ((functionId == TSDB_FUNC_LAST_DST || functionId == TSDB_FUNC_LAST)) {
     return pCtx->param[0].i64Key == pQuery->order.order;
-//    return !QUERY_IS_ASC_QUERY(pQuery);
   }
 
   // in the supplementary scan, only the following functions need to be executed
@@ -4716,8 +4715,8 @@ static void multiTableQueryProcess(SQInfo *pQInfo) {
     el = scanMultiTableDataBlocks(pQInfo);
     qDebug("QInfo:%p reversed scan completed, elapsed time: %" PRId64 "ms", pQInfo, el);
 
-    doRestoreContext(pQInfo);
     doCloseAllTimeWindowAfterScan(pQInfo);
+    doRestoreContext(pQInfo);
   } else {
     qDebug("QInfo:%p no need to do reversed scan, query completed", pQInfo);
   }
diff --git a/src/query/src/qUtil.c b/src/query/src/qUtil.c
index 9541f283f0bf65abeedc4abf3e2c42d25cb83c5e..3b2b2bfff075d5f2accca2c0be79ba72ba87be74 100644
--- a/src/query/src/qUtil.c
+++ b/src/query/src/qUtil.c
@@ -180,19 +180,34 @@ void closeAllTimeWindow(SWindowResInfo *pWindowResInfo) {
 
 /*
  * remove the results that are not the FIRST time window that spreads beyond the
- * the last qualified time stamp in case of sliding query, which the sliding time is not equalled to the interval time
+ * the last qualified time stamp in case of sliding query, which the sliding time is not equalled to the interval time.
+ * NOTE: remove redundant, only when the result set order equals to traverse order
  */
 void removeRedundantWindow(SWindowResInfo *pWindowResInfo, TSKEY lastKey, int32_t order) {
   assert(pWindowResInfo->size >= 0 && pWindowResInfo->capacity >= pWindowResInfo->size);
-  
+  if (pWindowResInfo->size <= 1) {
+    return;
+  }
+
+  // get the result order
+  int32_t resultOrder = (pWindowResInfo->pResult[0].window.skey < pWindowResInfo->pResult[1].window.skey)?
+                         TSDB_ORDER_ASC:TSDB_ORDER_DESC;
+
+  if (order != resultOrder) {
+    return;
+  }
+
   int32_t i = 0;
-  while (i < pWindowResInfo->size &&
-      ((pWindowResInfo->pResult[i].window.ekey < lastKey && order == QUERY_ASC_FORWARD_STEP) ||
-          (pWindowResInfo->pResult[i].window.skey > lastKey && order == QUERY_DESC_FORWARD_STEP))) {
-    ++i;
+  if (order == QUERY_ASC_FORWARD_STEP) {
+    while (i < pWindowResInfo->size && (pWindowResInfo->pResult[i].window.ekey < lastKey)) {
+      ++i;
+    }
+  } else if (order == QUERY_DESC_FORWARD_STEP) {
+    while (i < pWindowResInfo->size && (pWindowResInfo->pResult[i].window.skey > lastKey)) {
+      ++i;
+    }
   }
-  
-  //  assert(i < pWindowResInfo->size);
+
   if (i < pWindowResInfo->size) {
     pWindowResInfo->size = (i + 1);
   }
diff --git a/src/query/src/qextbuffer.c b/src/query/src/qextbuffer.c
index ce3f60c072585f800b09a13d82a55a14112ed819..afcf90212366cea331ba100d4c4a8974102d5fc5 100644
--- a/src/query/src/qextbuffer.c
+++ b/src/query/src/qextbuffer.c
@@ -118,7 +118,7 @@ static bool tExtMemBufferAlloc(tExtMemBuffer *pMemBuffer) {
    * To flush data to disk to accommodate more data
    */
   if (pMemBuffer->numOfInMemPages > 0 && pMemBuffer->numOfInMemPages == pMemBuffer->inMemCapacity) {
-    if (!tExtMemBufferFlush(pMemBuffer)) {
+    if (tExtMemBufferFlush(pMemBuffer) != 0) {
       return false;
     }
   }
@@ -268,6 +268,7 @@ int32_t tExtMemBufferFlush(tExtMemBuffer *pMemBuffer) {
     size_t retVal = fwrite((char *)&(first->item), pMemBuffer->pageSize, 1, pMemBuffer->file);
     if (retVal <= 0) {  // failed to write to buffer, may be not enough space
       ret = TAOS_SYSTEM_ERROR(errno);
+      return ret;
     }
 
     pMemBuffer->fileMeta.numOfElemsInFile += first->item.num;
diff --git a/src/tsdb/src/tsdbMeta.c b/src/tsdb/src/tsdbMeta.c
index ad25b7f675a3cdf0e3fce0a5b33e6a4bc941e3d1..8b79d95af11f03317bc4949060b1ba3d5920f90b 100644
--- a/src/tsdb/src/tsdbMeta.c
+++ b/src/tsdb/src/tsdbMeta.c
@@ -274,6 +274,8 @@ int tsdbUpdateTagValue(TSDB_REPO_T *repo, SUpdateTableTagValMsg *pMsg) {
   pMsg->tid = htonl(pMsg->tid);
   pMsg->tversion  = htons(pMsg->tversion);
   pMsg->colId     = htons(pMsg->colId);
+  pMsg->type      = htons(pMsg->type);
+  pMsg->bytes     = htons(pMsg->bytes);
   pMsg->tagValLen = htonl(pMsg->tagValLen);
   pMsg->numOfTags = htons(pMsg->numOfTags);
   pMsg->schemaLen = htonl(pMsg->schemaLen);