diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index ec4f77b13e6d6ee3ecf449265f9a4c9a79ff9ff3..51221766ce52b764e69981a2d075991a11ceb7da 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -654,11 +654,14 @@ int32_t parseIntervalClause(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SQuerySQL* pQ
 int32_t parseSlidingClause(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SQuerySQL* pQuerySql) {
   const char* msg0 = "sliding value too small";
   const char* msg1 = "sliding value no larger than the interval value";
+  const char* msg2 = "sliding value can not less than 1% of interval value";
+
+  const static int32_t INTERVAL_SLIDING_FACTOR = 100;
 
   STableMetaInfo* pTableMetaInfo = tscGetMetaInfo(pQueryInfo, 0);
-  SSQLToken*      pSliding = &pQuerySql->sliding;
   STableComInfo tinfo = tscGetTableInfo(pTableMetaInfo->pTableMeta);
 
+  SSQLToken* pSliding = &pQuerySql->sliding;
   if (pSliding->n != 0) {
     getTimestampInUsFromStr(pSliding->z, pSliding->n, &pQueryInfo->slidingTime);
     if (tinfo.precision == TSDB_TIME_PRECISION_MILLI) {
@@ -676,6 +679,10 @@ int32_t parseSlidingClause(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SQuerySQL* pQu
     pQueryInfo->slidingTime = pQueryInfo->intervalTime;
   }
 
+  if ((pQueryInfo->intervalTime != 0) && (pQueryInfo->intervalTime/pQueryInfo->slidingTime > INTERVAL_SLIDING_FACTOR)) {
+    return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg2);
+  }
+
   return TSDB_CODE_SUCCESS;
 }
 
diff --git a/src/common/src/tname.c b/src/common/src/tname.c
index dd0107bf3816ab120ee1b195e46ef971ce78f6a0..8b85ecfbc79e0cd3b180c53abcaed73dfa3b6e15 100644
--- a/src/common/src/tname.c
+++ b/src/common/src/tname.c
@@ -81,7 +81,7 @@ int64_t taosGetIntervalStartTimestamp(int64_t startTime, int64_t slidingTime, in
     return startTime;
   }
 
-  int64_t start = ((startTime - slidingTime) / slidingTime + 1) * slidingTime;
+  int64_t start = ((startTime - intervalTime) / slidingTime + 1) * slidingTime;
   if (!(timeUnit == 'a' || timeUnit == 'm' || timeUnit == 's' || timeUnit == 'h')) {
     /*
      * here we revised the start time of day according to the local time zone,
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index fcf0a1a89d3c5f20deb70a9f6b876f0f08a1972f..25fcba77315e870a2a2672020847ee95e2d002ad 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -2294,10 +2294,10 @@ static int64_t doScanAllDataBlocks(SQueryRuntimeEnv *pRuntimeEnv) {
 
   if (QUERY_IS_INTERVAL_QUERY(pQuery) && IS_MASTER_SCAN(pRuntimeEnv)) {
     if (Q_STATUS_EQUAL(pQuery->status, QUERY_COMPLETED)) {
-      int32_t step = QUERY_IS_ASC_QUERY(pQuery) ? QUERY_ASC_FORWARD_STEP : QUERY_DESC_FORWARD_STEP;
+//      int32_t step = QUERY_IS_ASC_QUERY(pQuery) ? QUERY_ASC_FORWARD_STEP : QUERY_DESC_FORWARD_STEP;
 
       closeAllTimeWindow(&pRuntimeEnv->windowResInfo);
-      removeRedundantWindow(&pRuntimeEnv->windowResInfo, pTableQueryInfo->lastKey - step, step);
+//      removeRedundantWindow(&pRuntimeEnv->windowResInfo, pTableQueryInfo->lastKey - step, step);
       pRuntimeEnv->windowResInfo.curIndex = pRuntimeEnv->windowResInfo.size - 1;  // point to the last time window
     } else {
       assert(Q_STATUS_EQUAL(pQuery->status, QUERY_RESBUF_FULL));
@@ -2914,6 +2914,9 @@ static void updateTableQueryInfoForReverseScan(SQuery *pQuery, STableQueryInfo *
   
   SWITCH_ORDER(pTableQueryInfo->cur.order);
   pTableQueryInfo->cur.vgroupIndex = -1;
+
+  // set the index at the end of time window
+  pTableQueryInfo->windowResInfo.curIndex = pTableQueryInfo->windowResInfo.size - 1;
 }
 
 static void disableFuncInReverseScanImpl(SQInfo* pQInfo, SWindowResInfo *pWindowResInfo, int32_t order) {
@@ -4690,7 +4693,7 @@ static void doRestoreContext(SQInfo *pQInfo) {
 static void doCloseAllTimeWindowAfterScan(SQInfo *pQInfo) {
   SQuery *pQuery = pQInfo->runtimeEnv.pQuery;
 
-  int32_t step = GET_FORWARD_DIRECTION_FACTOR(pQuery->order.order);
+//  int32_t step = GET_FORWARD_DIRECTION_FACTOR(pQuery->order.order);
 
   if (QUERY_IS_INTERVAL_QUERY(pQuery)) {
     size_t numOfGroup = GET_NUM_OF_TABLEGROUP(pQInfo);
@@ -4701,7 +4704,7 @@ static void doCloseAllTimeWindowAfterScan(SQInfo *pQInfo) {
       for (int32_t j = 0; j < num; ++j) {
         STableQueryInfo* item = taosArrayGetP(group, j);
         closeAllTimeWindow(&item->windowResInfo);
-        removeRedundantWindow(&item->windowResInfo, item->lastKey - step, step);
+//        removeRedundantWindow(&item->windowResInfo, item->lastKey - step, step);
       }
     }
   } else {  // close results for group result
@@ -4753,7 +4756,7 @@ static void multiTableQueryProcess(SQInfo *pQInfo) {
     el = scanMultiTableDataBlocks(pQInfo);
     qDebug("QInfo:%p reversed scan completed, elapsed time: %" PRId64 "ms", pQInfo, el);
 
-    doCloseAllTimeWindowAfterScan(pQInfo);
+//    doCloseAllTimeWindowAfterScan(pQInfo);
     doRestoreContext(pQInfo);
   } else {
     qDebug("QInfo:%p no need to do reversed scan, query completed", pQInfo);