diff --git a/include/libs/function/function.h b/include/libs/function/function.h
index 60c7b18367ea9bc90c441ab005f85931106aecf3..1796956f96ea6f2e8b42eaf637bf371167f1fa2c 100644
--- a/include/libs/function/function.h
+++ b/include/libs/function/function.h
@@ -54,7 +54,7 @@ typedef struct SFuncExecFuncs {
   FExecCombine  combine;
 } SFuncExecFuncs;
 
-#define MAX_INTERVAL_TIME_WINDOW 1000000  // maximum allowed time windows in final results
+#define MAX_INTERVAL_TIME_WINDOW 10000000  // maximum allowed time windows in final results
 
 #define TOP_BOTTOM_QUERY_LIMIT    100
 #define FUNCTIONS_NAME_MAX_LENGTH 16
diff --git a/source/dnode/vnode/src/tsdb/tsdbMergeTree.c b/source/dnode/vnode/src/tsdb/tsdbMergeTree.c
index bf94ae68ffdf35a263b0cda82462304f7b2480d3..4a6f6777875a7c7a5e855f2a57db38383d3d0d15 100644
--- a/source/dnode/vnode/src/tsdb/tsdbMergeTree.c
+++ b/source/dnode/vnode/src/tsdb/tsdbMergeTree.c
@@ -265,24 +265,43 @@ int32_t tLDataIterOpen(struct SLDataIter **pIter, SDataFReader *pReader, int32_t
 
     // only apply to the child tables, ordinary tables will not incur this filter procedure.
     size = taosArrayGetSize(pBlockLoadInfo->aSttBlk);
-    SArray *pTmp = taosArrayInit(size, sizeof(SSttBlk));
-    for (int32_t i = 0; i < size; ++i) {
-      SSttBlk *p = taosArrayGet(pBlockLoadInfo->aSttBlk, i);
-      uint64_t s = p->suid;
-      if (s < suid) {
-        continue;
-      }
 
-      if (s == suid) {
-        taosArrayPush(pTmp, p);
-      } else if (s > suid) {
-        break;
+    if (size > 1) {
+      SSttBlk *pStart = taosArrayGet(pBlockLoadInfo->aSttBlk, 0);
+      SSttBlk *pEnd = taosArrayGet(pBlockLoadInfo->aSttBlk, size - 1);
+
+      // all identical
+      if (pStart->suid == pEnd->suid) {
+        if (pStart->suid == suid) {
+          // do nothing
+        } else if (pStart->suid != suid) {
+          // no qualified stt block existed
+          (*pIter)->iSttBlk = -1;
+          double el = (taosGetTimestampUs() - st)/1000.0;
+          tsdbDebug("load the last file info completed, elapsed time:%.2fms, %s", el, idStr);
+          return code;
+        }
+      } else {
+        SArray *pTmp = taosArrayInit(size, sizeof(SSttBlk));
+        for (int32_t i = 0; i < size; ++i) {
+          SSttBlk *p = taosArrayGet(pBlockLoadInfo->aSttBlk, i);
+          uint64_t s = p->suid;
+          if (s < suid) {
+            continue;
+          }
+
+          if (s == suid) {
+            taosArrayPush(pTmp, p);
+          } else if (s > suid) {
+            break;
+          }
+        }
+
+        taosArrayDestroy(pBlockLoadInfo->aSttBlk);
+        pBlockLoadInfo->aSttBlk = pTmp;
       }
     }
 
-    taosArrayDestroy(pBlockLoadInfo->aSttBlk);
-    pBlockLoadInfo->aSttBlk = pTmp;
-
     double el = (taosGetTimestampUs() - st)/1000.0;
     tsdbDebug("load the last file info completed, elapsed time:%.2fms, %s", el, idStr);
   }
diff --git a/source/libs/function/src/builtins.c b/source/libs/function/src/builtins.c
index e9415dc87978872ad672c160aae68e194052443c..2308aaf214888c27f8ebb40071dd54cd027d523d 100644
--- a/source/libs/function/src/builtins.c
+++ b/source/libs/function/src/builtins.c
@@ -662,7 +662,7 @@ static int32_t translateTopBot(SFunctionNode* pFunc, char* pErrBuf, int32_t len)
     return invaildFuncParaTypeErrMsg(pErrBuf, len, pFunc->functionName);
   }
 
-  if (pValue->datum.i < 1 || pValue->datum.i > 100) {
+  if (pValue->datum.i < 1 || pValue->datum.i > TOP_BOTTOM_QUERY_LIMIT) {
     return invaildFuncParaValueErrMsg(pErrBuf, len, pFunc->functionName);
   }