diff --git a/source/dnode/vnode/src/tsdb/tsdbCache.c b/source/dnode/vnode/src/tsdb/tsdbCache.c
index e259dde29c86a7559d8d4dd5f256a81dc137727b..46de219035a36ae6c40c4e8e1ac8bb4cc777d6f7 100644
--- a/source/dnode/vnode/src/tsdb/tsdbCache.c
+++ b/source/dnode/vnode/src/tsdb/tsdbCache.c
@@ -46,10 +46,10 @@ void tsdbCloseCache(SLRUCache *pCache) {
   }
 }
 
-static void getTableCacheKeyS(tb_uid_t uid, const char *cacheType, char *key, int *len) {
-  snprintf(key, 30, "%" PRIi64 "%s", uid, cacheType);
-  *len = strlen(key);
-}
+/* static void getTableCacheKeyS(tb_uid_t uid, const char *cacheType, char *key, int *len) { */
+/*   snprintf(key, 30, "%" PRIi64 "%s", uid, cacheType); */
+/*   *len = strlen(key); */
+/* } */
 
 static void getTableCacheKey(tb_uid_t uid, int cacheType, char *key, int *len) {
   if (cacheType == 0) {  // last_row
@@ -245,8 +245,6 @@ int32_t tsdbCacheInsertLast(SLRUCache *pCache, tb_uid_t uid, STSRow *row, STsdb
   char    key[32] = {0};
   int     keyLen = 0;
 
-  // ((void)(row));
-
   // getTableCacheKey(uid, "l", key, &keyLen);
   getTableCacheKey(uid, 1, key, &keyLen);
   LRUHandle *h = taosLRUCacheLookup(pCache, key, keyLen);
@@ -323,26 +321,10 @@ static tb_uid_t getTableSuidByUid(tb_uid_t uid, STsdb *pTsdb) {
 static int32_t getTableDelDataFromDelIdx(SDelFReader *pDelReader, SDelIdx *pDelIdx, SArray *aDelData) {
   int32_t code = 0;
 
-  // SMapData delDataMap;
-  // SDelData delData;
-
   if (pDelIdx) {
-    // tMapDataReset(&delDataMap);
-
-    // code = tsdbReadDelData(pDelReader, pDelIdx, &delDataMap, NULL);
     code = tsdbReadDelData(pDelReader, pDelIdx, aDelData, NULL);
-    if (code) goto _err;
-    /*
-    for (int32_t iDelData = 0; iDelData < delDataMap.nItem; ++iDelData) {
-      code = tMapDataGetItemByIdx(&delDataMap, iDelData, &delData, tGetDelData);
-      if (code) goto _err;
-
-      taosArrayPush(aDelData, &delData);
-    }
-    */
   }
 
-_err:
   return code;
 }
 
@@ -444,18 +426,16 @@ typedef struct SFSNextRowIter {
   SArray          *aDFileSet;
   SDataFReader    *pDataFReader;
   SArray          *aBlockIdx;
-  // SMapData         blockIdxMap;
-  //  SBlockIdx  blockIdx;
-  SBlockIdx  *pBlockIdx;
-  SMapData    blockMap;
-  int32_t     nBlock;
-  int32_t     iBlock;
-  SBlock      block;
-  SBlockData  blockData;
-  SBlockData *pBlockData;
-  int32_t     nRow;
-  int32_t     iRow;
-  TSDBROW     row;
+  SBlockIdx       *pBlockIdx;
+  SMapData         blockMap;
+  int32_t          nBlock;
+  int32_t          iBlock;
+  SBlock           block;
+  SBlockData       blockData;
+  SBlockData      *pBlockData;
+  int32_t          nRow;
+  int32_t          iRow;
+  TSDBROW          row;
 } SFSNextRowIter;
 
 static int32_t getNextRowFromFS(void *iter, TSDBROW **ppRow) {
@@ -629,41 +609,8 @@ typedef struct SMemNextRowIter {
 } SMemNextRowIter;
 
 static int32_t getNextRowFromMem(void *iter, TSDBROW **ppRow) {
-  // static int32_t getNextRowFromMem(void *iter, SArray *pRowArray) {
   SMemNextRowIter *state = (SMemNextRowIter *)iter;
   int32_t          code = 0;
-  /*
-  if (!state->iterOpened) {
-    if (state->pMem != NULL) {
-      tsdbTbDataIterOpen(state->pMem, NULL, 1, &state->iter);
-
-      state->iterOpened = true;
-
-      TSDBROW *pMemRow = tsdbTbDataIterGet(&state->iter);
-      if (pMemRow) {
-        state->curRow = pMemRow;
-      } else {
-        return code;
-      }
-    } else {
-      return code;
-    }
-  }
-
-  taosArrayPush(pRowArray, state->curRow);
-  while (tsdbTbDataIterNext(&state->iter)) {
-    TSDBROW *row = tsdbTbDataIterGet(&state->iter);
-
-    if (TSDBROW_TS(row) < TSDBROW_TS(state->curRow)) {
-      state->curRow = row;
-      break;
-    } else {
-      taosArrayPush(pRowArray, row);
-    }
-  }
-
-  return code;
-  */
   switch (state->state) {
     case SMEMNEXTROW_ENTER: {
       if (state->pMem != NULL) {
@@ -768,10 +715,8 @@ static bool tsdbKeyDeleted(TSDBKEY *key, SArray *pSkyline, int64_t *iSkyline) {
 }
 
 typedef int32_t (*_next_row_fn_t)(void *iter, TSDBROW **ppRow);
-// typedef int32_t (*_next_row_fn_t)(void *iter, SArray *pRowArray);
 typedef int32_t (*_next_row_clear_fn_t)(void *iter);
 
-// typedef struct TsdbNextRowState {
 typedef struct {
   TSDBROW             *pRow;
   bool                 stop;
@@ -782,7 +727,6 @@ typedef struct {
 } TsdbNextRowState;
 
 typedef struct {
-  // STsdb  *pTsdb;
   SArray *pSkyline;
   int64_t iSkyline;
 
@@ -793,10 +737,8 @@ typedef struct {
   TSDBROW         memRow, imemRow, fsRow;
 
   TsdbNextRowState input[3];
-  // SMemTable       *pMemTable;
-  // SMemTable       *pIMemTable;
-  STsdbReadSnap *pReadSnap;
-  STsdb         *pTsdb;
+  STsdbReadSnap   *pReadSnap;
+  STsdb           *pTsdb;
 } CacheNextRowIter;
 
 static int32_t nextRowIterOpen(CacheNextRowIter *pIter, tb_uid_t uid, STsdb *pTsdb) {
@@ -967,7 +909,7 @@ _err:
   return code;
 }
 
-static int32_t mergeLastRow2(tb_uid_t uid, STsdb *pTsdb, bool *dup, STSRow **ppRow) {
+static int32_t mergeLastRow(tb_uid_t uid, STsdb *pTsdb, bool *dup, STSRow **ppRow) {
   int32_t code = 0;
 
   STSchema *pTSchema = metaGetTbTSchema(pTsdb->pVnode->pMeta, uid, -1);
@@ -978,8 +920,6 @@ static int32_t mergeLastRow2(tb_uid_t uid, STsdb *pTsdb, bool *dup, STSRow **ppR
   SArray   *pColArray = taosArrayInit(nCol, sizeof(SColVal));
   SColVal  *pColVal = &(SColVal){0};
 
-  // tb_uid_t suid = getTableSuidByUid(uid, pTsdb);
-
   TSKEY lastRowTs = TSKEY_MAX;
 
   CacheNextRowIter iter = {0};
@@ -1066,7 +1006,7 @@ _err:
   return code;
 }
 
-static int32_t mergeLast2(tb_uid_t uid, STsdb *pTsdb, SArray **ppLastArray) {
+static int32_t mergeLast(tb_uid_t uid, STsdb *pTsdb, SArray **ppLastArray) {
   int32_t code = 0;
 
   STSchema *pTSchema = metaGetTbTSchema(pTsdb->pVnode->pMeta, uid, -1);
@@ -1077,8 +1017,6 @@ static int32_t mergeLast2(tb_uid_t uid, STsdb *pTsdb, SArray **ppLastArray) {
   SArray   *pColArray = taosArrayInit(nCol, sizeof(SLastCol));
   SColVal  *pColVal = &(SColVal){0};
 
-  // tb_uid_t suid = getTableSuidByUid(uid, pTsdb);
-
   TSKEY lastRowTs = TSKEY_MAX;
 
   CacheNextRowIter iter = {0};
@@ -1124,12 +1062,7 @@ static int32_t mergeLast2(tb_uid_t uid, STsdb *pTsdb, SArray **ppLastArray) {
         continue;
       }
     }
-    /*
-    if ((TSDBROW_TS(pRow) < lastRowTs)) {
-      // goto build the result ts row
-      break;
-    }
-    */
+
     // merge into pColArray
     setNoneCol = false;
     for (iCol = noneCol; iCol < nCol; ++iCol) {
@@ -1139,7 +1072,6 @@ static int32_t mergeLast2(tb_uid_t uid, STsdb *pTsdb, SArray **ppLastArray) {
       tsdbRowGetColVal(pRow, pTSchema, iCol, pColVal);
       if ((tColVal->isNone || tColVal->isNull) && (!pColVal->isNone && !pColVal->isNull)) {
         taosArraySet(pColArray, iCol, &(SLastCol){.ts = rowTs, .colVal = *pColVal});
-        //} else if (tColVal->isNone && pColVal->isNone && !setNoneCol) {
       } else if ((tColVal->isNone || tColVal->isNull) && (pColVal->isNone || pColVal->isNull) && !setNoneCol) {
         noneCol = iCol;
         setNoneCol = true;
@@ -1148,521 +1080,36 @@ static int32_t mergeLast2(tb_uid_t uid, STsdb *pTsdb, SArray **ppLastArray) {
   } while (setNoneCol);
 
   // build the result ts row here
-  //*dup = false;
   if (taosArrayGetSize(pColArray) <= 0) {
     *ppLastArray = NULL;
     taosArrayDestroy(pColArray);
   } else {
     *ppLastArray = pColArray;
   }
-  /*  if (taosArrayGetSize(pColArray) == nCol) {
-    code = tdSTSRowNew(pColArray, pTSchema, ppRow);
-    if (code) goto _err;
-  } else {
-    *ppRow = NULL;
-    }*/
 
   nextRowIterClose(&iter);
-  // taosArrayDestroy(pColArray);
   taosMemoryFreeClear(pTSchema);
   return code;
 
 _err:
   nextRowIterClose(&iter);
-  // taosArrayDestroy(pColArray);
   taosMemoryFreeClear(pTSchema);
   return code;
 }
 
-// static int32_t mergeLastRow(tb_uid_t uid, STsdb *pTsdb, bool *dup, STSRow **ppRow) {
-//   int32_t code = 0;
-//   SArray *pSkyline = NULL;
-
-//   STSchema *pTSchema = metaGetTbTSchema(pTsdb->pVnode->pMeta, uid, -1);
-//   int16_t   nCol = pTSchema->numOfCols;
-//   SArray   *pColArray = taosArrayInit(nCol, sizeof(SColVal));
-
-//   tb_uid_t suid = getTableSuidByUid(uid, pTsdb);
-
-//   STbData *pMem = NULL;
-//   if (pTsdb->mem) {
-//     tsdbGetTbDataFromMemTable(pTsdb->mem, suid, uid, &pMem);
-//   }
-
-//   STbData *pIMem = NULL;
-//   if (pTsdb->imem) {
-//     tsdbGetTbDataFromMemTable(pTsdb->imem, suid, uid, &pIMem);
-//   }
-
-//   *ppRow = NULL;
-
-//   pSkyline = taosArrayInit(32, sizeof(TSDBKEY));
-
-//   SDelIdx delIdx;
-
-//   SDelFile *pDelFile = tsdbFSStateGetDelFile(pTsdb->pFS->cState);
-//   if (pDelFile) {
-//     SDelFReader *pDelFReader;
-
-//     code = tsdbDelFReaderOpen(&pDelFReader, pDelFile, pTsdb, NULL);
-//     if (code) goto _err;
-
-//     code = getTableDelIdx(pDelFReader, suid, uid, &delIdx);
-//     if (code) goto _err;
-
-//     code = getTableDelSkyline(pMem, pIMem, pDelFReader, &delIdx, pSkyline);
-//     if (code) goto _err;
-
-//     tsdbDelFReaderClose(&pDelFReader);
-//   } else {
-//     code = getTableDelSkyline(pMem, pIMem, NULL, NULL, pSkyline);
-//     if (code) goto _err;
-//   }
-
-//   int64_t iSkyline = taosArrayGetSize(pSkyline) - 1;
-
-//   SBlockIdx idx = {.suid = suid, .uid = uid};
-
-//   SFSNextRowIter fsState = {0};
-//   fsState.state = SFSNEXTROW_FS;
-//   fsState.pTsdb = pTsdb;
-//   fsState.pBlockIdxExp = &idx;
-
-//   SMemNextRowIter memState = {0};
-//   SMemNextRowIter imemState = {0};
-//   TSDBROW         memRow, imemRow, fsRow;
-
-//   TsdbNextRowState input[3] = {{&memRow, true, false, &memState, getNextRowFromMem, NULL},
-//                                {&imemRow, true, false, &imemState, getNextRowFromMem, NULL},
-//                                {&fsRow, false, true, &fsState, getNextRowFromFS, clearNextRowFromFS}};
-
-//   if (pMem) {
-//     memState.pMem = pMem;
-//     memState.state = SMEMNEXTROW_ENTER;
-//     input[0].stop = false;
-//     input[0].next = true;
-//   }
-//   if (pIMem) {
-//     imemState.pMem = pIMem;
-//     imemState.state = SMEMNEXTROW_ENTER;
-//     input[1].stop = false;
-//     input[1].next = true;
-//   }
-
-//   int16_t nilColCount = nCol - 1;  // count of null & none cols
-//   int     iCol = 0;                // index of first nil col index from left to right
-//   bool    setICol = false;
-
-//   do {
-//     for (int i = 0; i < 3; ++i) {
-//       if (input[i].next && !input[i].stop) {
-//         if (input[i].pRow == NULL) {
-//           code = input[i].nextRowFn(input[i].iter, &input[i].pRow);
-//           if (code) goto _err;
-
-//           if (input[i].pRow == NULL) {
-//             input[i].stop = true;
-//             input[i].next = false;
-//           }
-//         }
-//       }
-//     }
-
-//     if (input[0].stop && input[1].stop && input[2].stop) {
-//       break;
-//     }
-
-//     // select maxpoint(s) from mem, imem, fs
-//     TSDBROW *max[3] = {0};
-//     int      iMax[3] = {-1, -1, -1};
-//     int      nMax = 0;
-//     TSKEY    maxKey = TSKEY_MIN;
-
-//     for (int i = 0; i < 3; ++i) {
-//       if (!input[i].stop && input[i].pRow != NULL) {
-//         TSDBKEY key = TSDBROW_KEY(input[i].pRow);
-
-//         // merging & deduplicating on client side
-//         if (maxKey <= key.ts) {
-//           if (maxKey < key.ts) {
-//             nMax = 0;
-//             maxKey = key.ts;
-//           }
-
-//           iMax[nMax] = i;
-//           max[nMax++] = input[i].pRow;
-//         }
-//       }
-//     }
-
-//     // delete detection
-//     TSDBROW *merge[3] = {0};
-//     int      iMerge[3] = {-1, -1, -1};
-//     int      nMerge = 0;
-//     for (int i = 0; i < nMax; ++i) {
-//       TSDBKEY maxKey = TSDBROW_KEY(max[i]);
-
-//       bool deleted = tsdbKeyDeleted(&maxKey, pSkyline, &iSkyline);
-//       if (!deleted) {
-//         iMerge[nMerge] = i;
-//         merge[nMerge++] = max[i];
-//       }
-
-//       input[iMax[i]].next = deleted;
-//     }
-
-//     // merge if nMerge > 1
-//     if (nMerge > 0) {
-//       *dup = false;
-
-//       if (nMerge == 1) {
-//         code = tsRowFromTsdbRow(pTSchema, merge[nMerge - 1], ppRow);
-//         if (code) goto _err;
-//       } else {
-//         // merge 2 or 3 rows
-//         SRowMerger merger = {0};
-
-//         tRowMergerInit(&merger, merge[0], pTSchema);
-//         for (int i = 1; i < nMerge; ++i) {
-//           tRowMerge(&merger, merge[i]);
-//         }
-//         tRowMergerGetRow(&merger, ppRow);
-//         tRowMergerClear(&merger);
-//       }
-//     }
-
-//   } while (1);
-
-//   for (int i = 0; i < 3; ++i) {
-//     if (input[i].nextRowClearFn) {
-//       input[i].nextRowClearFn(input[i].iter);
-//     }
-//   }
-//   if (pSkyline) {
-//     taosArrayDestroy(pSkyline);
-//   }
-//   taosMemoryFreeClear(pTSchema);
-
-//   return code;
-// _err:
-//   for (int i = 0; i < 3; ++i) {
-//     if (input[i].nextRowClearFn) {
-//       input[i].nextRowClearFn(input[i].iter);
-//     }
-//   }
-//   if (pSkyline) {
-//     taosArrayDestroy(pSkyline);
-//   }
-//   taosMemoryFreeClear(pTSchema);
-//   tsdbError("vgId:%d merge last_row failed since %s", TD_VID(pTsdb->pVnode), tstrerror(code));
-//   return code;
-// }
-
-// static int32_t mergeLast(tb_uid_t uid, STsdb *pTsdb, STSRow **ppRow) {
-// static int32_t mergeLast(tb_uid_t uid, STsdb *pTsdb, SArray **ppLastArray) {
-//   int32_t  code = 0;
-//   SArray  *pSkyline = NULL;
-//   STSRow  *pRow = NULL;
-//   STSRow **ppRow = &pRow;
-
-//   STSchema *pTSchema = metaGetTbTSchema(pTsdb->pVnode->pMeta, uid, -1);
-//   int16_t   nCol = pTSchema->numOfCols;
-//   //  SArray   *pColArray = taosArrayInit(nCol, sizeof(SColVal));
-//   SArray *pColArray = taosArrayInit(nCol, sizeof(SLastCol));
-
-//   tb_uid_t suid = getTableSuidByUid(uid, pTsdb);
-
-//   STbData *pMem = NULL;
-//   if (pTsdb->mem) {
-//     tsdbGetTbDataFromMemTable(pTsdb->mem, suid, uid, &pMem);
-//   }
-
-//   STbData *pIMem = NULL;
-//   if (pTsdb->imem) {
-//     tsdbGetTbDataFromMemTable(pTsdb->imem, suid, uid, &pIMem);
-//   }
-
-//   *ppLastArray = NULL;
-
-//   pSkyline = taosArrayInit(32, sizeof(TSDBKEY));
-
-//   SDelIdx delIdx;
-
-//   SDelFile *pDelFile = tsdbFSStateGetDelFile(pTsdb->pFS->cState);
-//   if (pDelFile) {
-//     SDelFReader *pDelFReader;
-
-//     code = tsdbDelFReaderOpen(&pDelFReader, pDelFile, pTsdb, NULL);
-//     if (code) goto _err;
-
-//     code = getTableDelIdx(pDelFReader, suid, uid, &delIdx);
-//     if (code) goto _err;
-
-//     code = getTableDelSkyline(pMem, pIMem, pDelFReader, &delIdx, pSkyline);
-//     if (code) goto _err;
-
-//     tsdbDelFReaderClose(&pDelFReader);
-//   } else {
-//     code = getTableDelSkyline(pMem, pIMem, NULL, NULL, pSkyline);
-//     if (code) goto _err;
-//   }
-
-//   int64_t iSkyline = taosArrayGetSize(pSkyline) - 1;
-
-//   SBlockIdx idx = {.suid = suid, .uid = uid};
-
-//   SFSNextRowIter fsState = {0};
-//   fsState.state = SFSNEXTROW_FS;
-//   fsState.pTsdb = pTsdb;
-//   fsState.pBlockIdxExp = &idx;
-
-//   SMemNextRowIter memState = {0};
-//   SMemNextRowIter imemState = {0};
-//   TSDBROW         memRow, imemRow, fsRow;
-
-//   TsdbNextRowState input[3] = {{&memRow, true, false, &memState, getNextRowFromMem, NULL},
-//                                {&imemRow, true, false, &imemState, getNextRowFromMem, NULL},
-//                                {&fsRow, false, true, &fsState, getNextRowFromFS, clearNextRowFromFS}};
-
-//   if (pMem) {
-//     memState.pMem = pMem;
-//     memState.state = SMEMNEXTROW_ENTER;
-//     input[0].stop = false;
-//     input[0].next = true;
-//   }
-//   if (pIMem) {
-//     imemState.pMem = pIMem;
-//     imemState.state = SMEMNEXTROW_ENTER;
-//     input[1].stop = false;
-//     input[1].next = true;
-//   }
-
-//   int16_t nilColCount = nCol - 1;  // count of null & none cols
-//   int     iCol = 0;                // index of first nil col index from left to right
-//   bool    setICol = false;
-
-//   do {
-//     for (int i = 0; i < 3; ++i) {
-//       if (input[i].next && !input[i].stop) {
-//         code = input[i].nextRowFn(input[i].iter, &input[i].pRow);
-//         if (code) goto _err;
-
-//         if (input[i].pRow == NULL) {
-//           input[i].stop = true;
-//           input[i].next = false;
-//         }
-//       }
-//     }
-
-//     if (input[0].stop && input[1].stop && input[2].stop) {
-//       break;
-//     }
-
-//     // select maxpoint(s) from mem, imem, fs
-//     TSDBROW *max[3] = {0};
-//     int      iMax[3] = {-1, -1, -1};
-//     int      nMax = 0;
-//     TSKEY    maxKey = TSKEY_MIN;
-
-//     for (int i = 0; i < 3; ++i) {
-//       if (!input[i].stop && input[i].pRow != NULL) {
-//         TSDBKEY key = TSDBROW_KEY(input[i].pRow);
-
-//         // merging & deduplicating on client side
-//         if (maxKey <= key.ts) {
-//           if (maxKey < key.ts) {
-//             nMax = 0;
-//             maxKey = key.ts;
-//           }
-
-//           iMax[nMax] = i;
-//           max[nMax++] = input[i].pRow;
-//         }
-//       }
-//     }
-
-//     // delete detection
-//     TSDBROW *merge[3] = {0};
-//     int      iMerge[3] = {-1, -1, -1};
-//     int      nMerge = 0;
-//     for (int i = 0; i < nMax; ++i) {
-//       TSDBKEY maxKey = TSDBROW_KEY(max[i]);
-
-//       bool deleted = tsdbKeyDeleted(&maxKey, pSkyline, &iSkyline);
-//       if (!deleted) {
-//         iMerge[nMerge] = iMax[i];
-//         merge[nMerge++] = max[i];
-//       }
-
-//       input[iMax[i]].next = deleted;
-//     }
-
-//     // merge if nMerge > 1
-//     if (nMerge > 0) {
-//       if (nMerge == 1) {
-//         code = tsRowFromTsdbRow(pTSchema, merge[nMerge - 1], ppRow);
-//         if (code) goto _err;
-//       } else {
-//         // merge 2 or 3 rows
-//         SRowMerger merger = {0};
-
-//         tRowMergerInit(&merger, merge[0], pTSchema);
-//         for (int i = 1; i < nMerge; ++i) {
-//           tRowMerge(&merger, merge[i]);
-//         }
-//         tRowMergerGetRow(&merger, ppRow);
-//         tRowMergerClear(&merger);
-//       }
-//     } else {
-//       /* *ppRow = NULL; */
-//       /* return code; */
-//       continue;
-//     }
-
-//     if (iCol == 0) {
-//       STColumn *pTColumn = &pTSchema->columns[0];
-//       SColVal  *pColVal = &(SColVal){0};
-
-//       *pColVal = COL_VAL_VALUE(pTColumn->colId, pTColumn->type, (SValue){.ts = maxKey});
-
-//       // if (taosArrayPush(pColArray, pColVal) == NULL) {
-//       if (taosArrayPush(pColArray, &(SLastCol){.ts = maxKey, .colVal = *pColVal}) == NULL) {
-//         code = TSDB_CODE_OUT_OF_MEMORY;
-//         goto _err;
-//       }
-
-//       ++iCol;
-
-//       setICol = false;
-//       for (int16_t i = iCol; i < nCol; ++i) {
-//         // tsdbRowGetColVal(*ppRow, pTSchema, i, pColVal);
-//         tTSRowGetVal(*ppRow, pTSchema, i, pColVal);
-//         // if (taosArrayPush(pColArray, pColVal) == NULL) {
-//         if (taosArrayPush(pColArray, &(SLastCol){.ts = maxKey, .colVal = *pColVal}) == NULL) {
-//           code = TSDB_CODE_OUT_OF_MEMORY;
-//           goto _err;
-//         }
-
-//         if (pColVal->isNull || pColVal->isNone) {
-//           for (int j = 0; j < nMerge; ++j) {
-//             SColVal jColVal = {0};
-//             tsdbRowGetColVal(merge[j], pTSchema, i, &jColVal);
-//             if (jColVal.isNull || jColVal.isNone) {
-//               input[iMerge[j]].next = true;
-//             }
-//           }
-//           if (!setICol) {
-//             iCol = i;
-//             setICol = true;
-//           }
-//         } else {
-//           --nilColCount;
-//         }
-//       }
-
-//       if (*ppRow) {
-//         taosMemoryFreeClear(*ppRow);
-//       }
-
-//       continue;
-//     }
-
-//     setICol = false;
-//     for (int16_t i = iCol; i < nCol; ++i) {
-//       SColVal colVal = {0};
-//       tTSRowGetVal(*ppRow, pTSchema, i, &colVal);
-//       TSKEY rowTs = (*ppRow)->ts;
-
-//       // SColVal *tColVal = (SColVal *)taosArrayGet(pColArray, i);
-//       SLastCol *tTsVal = (SLastCol *)taosArrayGet(pColArray, i);
-//       SColVal  *tColVal = &tTsVal->colVal;
-
-//       if (!colVal.isNone && !colVal.isNull) {
-//         if (tColVal->isNull || tColVal->isNone) {
-//           // taosArraySet(pColArray, i, &colVal);
-//           taosArraySet(pColArray, i, &(SLastCol){.ts = rowTs, .colVal = colVal});
-//           --nilColCount;
-//         }
-//       } else {
-//         if ((tColVal->isNull || tColVal->isNone) && !setICol) {
-//           iCol = i;
-//           setICol = true;
-
-//           for (int j = 0; j < nMerge; ++j) {
-//             SColVal jColVal = {0};
-//             tsdbRowGetColVal(merge[j], pTSchema, i, &jColVal);
-//             if (jColVal.isNull || jColVal.isNone) {
-//               input[iMerge[j]].next = true;
-//             }
-//           }
-//         }
-//       }
-//     }
-
-//     if (*ppRow) {
-//       taosMemoryFreeClear(*ppRow);
-//     }
-//   } while (nilColCount > 0);
-
-//   // if () new ts row from pColArray if non empty
-//   /* if (taosArrayGetSize(pColArray) == nCol) { */
-//   /*   code = tdSTSRowNew(pColArray, pTSchema, ppRow); */
-//   /*   if (code) goto _err; */
-//   /* } */
-//   /* taosArrayDestroy(pColArray); */
-//   if (taosArrayGetSize(pColArray) <= 0) {
-//     *ppLastArray = NULL;
-//     taosArrayDestroy(pColArray);
-//   } else {
-//     *ppLastArray = pColArray;
-//   }
-//   if (*ppRow) {
-//     taosMemoryFreeClear(*ppRow);
-//   }
-
-//   for (int i = 0; i < 3; ++i) {
-//     if (input[i].nextRowClearFn) {
-//       input[i].nextRowClearFn(input[i].iter);
-//     }
-//   }
-//   if (pSkyline) {
-//     taosArrayDestroy(pSkyline);
-//   }
-//   taosMemoryFreeClear(pTSchema);
-
-//   return code;
-// _err:
-//   taosArrayDestroy(pColArray);
-//   if (*ppRow) {
-//     taosMemoryFreeClear(*ppRow);
-//   }
-//   for (int i = 0; i < 3; ++i) {
-//     if (input[i].nextRowClearFn) {
-//       input[i].nextRowClearFn(input[i].iter);
-//     }
-//   }
-//   if (pSkyline) {
-//     taosArrayDestroy(pSkyline);
-//   }
-//   taosMemoryFreeClear(pTSchema);
-//   tsdbError("vgId:%d merge last_row failed since %s", TD_VID(pTsdb->pVnode), tstrerror(code));
-//   return code;
-// }
-
 int32_t tsdbCacheGetLastrowH(SLRUCache *pCache, tb_uid_t uid, STsdb *pTsdb, LRUHandle **handle) {
   int32_t code = 0;
   char    key[32] = {0};
   int     keyLen = 0;
 
-  //  getTableCacheKey(uid, "lr", key, &keyLen);
+  //  getTableCacheKeyS(uid, "lr", key, &keyLen);
   getTableCacheKey(uid, 0, key, &keyLen);
   LRUHandle *h = taosLRUCacheLookup(pCache, key, keyLen);
   if (h) {
-    //*ppRow = (STSRow *)taosLRUCacheValue(pCache, h);
   } else {
     STSRow *pRow = NULL;
     bool    dup = false;  // which is always false for now
-    code = mergeLastRow2(uid, pTsdb, &dup, &pRow);
+    code = mergeLastRow(uid, pTsdb, &dup, &pRow);
     // if table's empty or error, return code of -1
     if (code < 0 || pRow == NULL) {
       if (!dup && pRow) {
@@ -1680,9 +1127,7 @@ int32_t tsdbCacheGetLastrowH(SLRUCache *pCache, tb_uid_t uid, STsdb *pTsdb, LRUH
       code = -1;
     }
 
-    //    tsdbCacheInsertLastrow(pCache, pTsdb, uid, pRow, dup);
     h = taosLRUCacheLookup(pCache, key, keyLen);
-    //*ppRow = (STSRow *)taosLRUCacheValue(pCache, h);
   }
 
   *handle = h;
@@ -1719,18 +1164,13 @@ int32_t tsdbCacheGetLastH(SLRUCache *pCache, tb_uid_t uid, STsdb *pTsdb, LRUHand
   char    key[32] = {0};
   int     keyLen = 0;
 
-  // getTableCacheKey(uid, "l", key, &keyLen);
+  // getTableCacheKeyS(uid, "l", key, &keyLen);
   getTableCacheKey(uid, 1, key, &keyLen);
   LRUHandle *h = taosLRUCacheLookup(pCache, key, keyLen);
   if (h) {
-    //*ppRow = (STSRow *)taosLRUCacheValue(pCache, h);
-
   } else {
-    // STSRow *pRow = NULL;
-    // code = mergeLast(uid, pTsdb, &pRow);
     SArray *pLastArray = NULL;
-    // code = mergeLast(uid, pTsdb, &pLastArray);
-    code = mergeLast2(uid, pTsdb, &pLastArray);
+    code = mergeLast(uid, pTsdb, &pLastArray);
     // if table's empty or error, return code of -1
     // if (code < 0 || pRow == NULL) {
     if (code < 0 || pLastArray == NULL) {
@@ -1746,7 +1186,6 @@ int32_t tsdbCacheGetLastH(SLRUCache *pCache, tb_uid_t uid, STsdb *pTsdb, LRUHand
     }
 
     h = taosLRUCacheLookup(pCache, key, keyLen);
-    //*ppRow = (STSRow *)taosLRUCacheValue(pCache, h);
   }
 
   *handle = h;