diff --git a/source/dnode/vnode/src/tsdb/tsdbMergeTree.c b/source/dnode/vnode/src/tsdb/tsdbMergeTree.c
index 184584c577..2048d0d7ba 100644
--- a/source/dnode/vnode/src/tsdb/tsdbMergeTree.c
+++ b/source/dnode/vnode/src/tsdb/tsdbMergeTree.c
@@ -742,8 +742,6 @@ int32_t tMergeTreeOpen2(SMergeTree *pMTree, int8_t backward, STsdb *pTsdb, uint6
     tRBTreeCreate(&pMTree->rbt, tLDataIterDescCmprFn);
   }
 
-//  pMTree->pLoadInfo = pBlockLoadInfo;
-//  pMTree->destroyLoadInfo = true;
   pMTree->ignoreEarlierTs = false;
 
   // todo handle other level of stt files, here only deal with the first level stt
diff --git a/source/dnode/vnode/src/tsdb/tsdbRead2.c b/source/dnode/vnode/src/tsdb/tsdbRead2.c
index d951f48d50..351089a3ed 100644
--- a/source/dnode/vnode/src/tsdb/tsdbRead2.c
+++ b/source/dnode/vnode/src/tsdb/tsdbRead2.c
@@ -2444,7 +2444,7 @@ static int32_t mergeFileBlockAndLastBlock(STsdbReader* pReader, SLastBlockReader
     // row in last file block
     TSDBROW fRow = tsdbRowFromBlockData(pBlockData, pDumpInfo->rowIndex);
     int64_t ts = getCurrentKeyInLastBlock(pLastBlockReader);
-    ASSERT(ts >= key);
+//    ASSERT(ts >= key);
 
     if (ASCENDING_TRAVERSE(pReader->order)) {
       if (key < ts) {  // imem, mem are all empty, file blocks (data blocks and last block) exist
@@ -2473,8 +2473,8 @@ static int32_t mergeFileBlockAndLastBlock(STsdbReader* pReader, SLastBlockReader
         taosMemoryFree(pTSRow);
         tsdbRowMergerClear(pMerger);
         return code;
-      } else {
-        return TSDB_CODE_SUCCESS;
+      } else {  // key > ts
+        return doMergeFileBlockAndLastBlock(pLastBlockReader, pReader, pBlockScanInfo, NULL, false);
       }
     } else {  // desc order
       return doMergeFileBlockAndLastBlock(pLastBlockReader, pReader, pBlockScanInfo, pBlockData, true);
@@ -2902,8 +2902,9 @@ int32_t mergeRowsInFileBlocks(SBlockData* pBlockData, STableBlockScanInfo* pBloc
   SRowMerger*         pMerger = &pReader->status.merger;
   SFileBlockDumpInfo* pDumpInfo = &pReader->status.fBlockDumpInfo;
   bool                copied = false;
-  int32_t             code = tryCopyDistinctRowFromFileBlock(pReader, pBlockData, key, pDumpInfo, &copied);
-  if (code) {
+
+  int32_t code = tryCopyDistinctRowFromFileBlock(pReader, pBlockData, key, pDumpInfo, &copied);
+  if (code != TSDB_CODE_SUCCESS) {
     return code;
   }
 
diff --git a/tests/system-test/1-insert/delete_stable.py b/tests/system-test/1-insert/delete_stable.py
index fb0c0c6ced..67561c51e5 100644
--- a/tests/system-test/1-insert/delete_stable.py
+++ b/tests/system-test/1-insert/delete_stable.py
@@ -24,6 +24,7 @@ from util.common import *
 from util.sqlset import TDSetSql
 
 class TDTestCase:
+    updatecfgDict = {'tsdbdebugFlag': 143}
     def init(self, conn, logSql, replicaVar=1):
         self.replicaVar = int(replicaVar)
         tdLog.debug("start to execute %s" % __file__)