diff --git a/include/common/tdataformat.h b/include/common/tdataformat.h
index 867115d16d..2d740c1af7 100644
--- a/include/common/tdataformat.h
+++ b/include/common/tdataformat.h
@@ -46,6 +46,7 @@ void    tTSchemaDestroy(STSchema *pTSchema);
 #define COL_VAL_NULL(CID)     ((SColVal){.cid = (CID), .isNull = 1})
 #define COL_VAL_VALUE(CID, V) ((SColVal){.cid = (CID), .value = (V)})
 
+int32_t tTSRowNew(SArray *pArray, STSchema *pTSchema, STSRow2 **ppRow);
 int32_t tTSRowClone(const STSRow2 *pRow, STSRow2 **ppRow);
 void    tTSRowFree(STSRow2 *pRow);
 void    tTSRowGet(STSRow2 *pRow, STSchema *pTSchema, int32_t iCol, SColVal *pColVal);
@@ -66,7 +67,7 @@ int32_t tTSRowBuilderGetRow(STSRowBuilder *pBuilder, const STSRow2 **ppRow);
 int32_t tTagNew(SArray *pArray, int32_t version, int8_t isJson, STag **ppTag);
 void    tTagFree(STag *pTag);
 bool    tTagGet(const STag *pTag, STagVal *pTagVal);
-char*   tTagValToData(const STagVal *pTagVal, bool isJson);
+char   *tTagValToData(const STagVal *pTagVal, bool isJson);
 int32_t tEncodeTag(SEncoder *pEncoder, const STag *pTag);
 int32_t tDecodeTag(SDecoder *pDecoder, STag **ppTag);
 int32_t tTagToValArray(const STag *pTag, SArray **ppArray);
@@ -153,7 +154,7 @@ struct STagVal {
   };
   int8_t type;
   union {
-    int64_t  i64;
+    int64_t i64;
     struct {
       uint32_t nData;
       uint8_t *pData;
@@ -161,7 +162,7 @@ struct STagVal {
   };
 };
 
-#define TD_TAG_JSON  ((int8_t)0x40)   // distinguish JSON string and JSON value with the highest bit
+#define TD_TAG_JSON  ((int8_t)0x40)  // distinguish JSON string and JSON value with the highest bit
 #define TD_TAG_LARGE ((int8_t)0x20)
 struct STag {
   int8_t  flags;
@@ -421,4 +422,3 @@ int32_t    tdMergeDataCols(SDataCols *target, SDataCols *source, int32_t rowsToM
 #endif
 
 #endif /*_TD_COMMON_DATA_FORMAT_H_*/
-
diff --git a/source/common/src/tdataformat.c b/source/common/src/tdataformat.c
index 77fc156492..c53a22b408 100644
--- a/source/common/src/tdataformat.c
+++ b/source/common/src/tdataformat.c
@@ -953,25 +953,6 @@ static void debugPrintTagVal(int8_t type, const void *val, int32_t vlen, const c
   }
 }
 
-// if (isLarge) {
-//   p = (uint8_t *)&((int16_t *)pTag->idx)[pTag->nTag];
-// } else {
-//   p = (uint8_t *)&pTag->idx[pTag->nTag];
-// }
-
-// (*ppArray) = taosArrayInit(pTag->nTag + 1, sizeof(STagVal));
-// if (*ppArray == NULL) {
-//   code = TSDB_CODE_OUT_OF_MEMORY;
-//   goto _err;
-// }
-
-// for (int16_t iTag = 0; iTag < pTag->nTag; iTag++) {
-//   if (isLarge) {
-//     offset = ((int16_t *)pTag->idx)[iTag];
-//   } else {
-//     offset = pTag->idx[iTag];
-//   }
-
 void debugPrintSTag(STag *pTag, const char *tag, int32_t ln) {
   int8_t   isJson = pTag->flags & TD_TAG_JSON;
   int8_t   isLarge = pTag->flags & TD_TAG_LARGE;
diff --git a/source/dnode/vnode/src/tsdb/tsdbMemTable2.c b/source/dnode/vnode/src/tsdb/tsdbMemTable2.c
index d1c26f085b..cd2e0b56ca 100644
--- a/source/dnode/vnode/src/tsdb/tsdbMemTable2.c
+++ b/source/dnode/vnode/src/tsdb/tsdbMemTable2.c
@@ -55,14 +55,10 @@ struct SMemTable {
 #define SL_MAX_LEVEL 5
 
 #define SL_NODE_SIZE(l)        (sizeof(SMemSkipListNode) + sizeof(SMemSkipListNode *) * (l)*2)
-#define SL_NODE_HALF_SIZE(l)   (sizeof(SMemSkipListNode) + sizeof(SMemSkipListNode *) * (l))
 #define SL_NODE_FORWARD(n, l)  ((n)->forwards[l])
 #define SL_NODE_BACKWARD(n, l) ((n)->forwards[(n)->level + (l)])
 #define SL_NODE_DATA(n)        (&SL_NODE_BACKWARD(n, (n)->level))
 
-#define SL_HEAD_FORWARD(sl, l)  SL_NODE_FORWARD((sl)->pHead, l)
-#define SL_TAIL_BACKWARD(sl, l) SL_NODE_FORWARD((sl)->pTail, l)
-
 static int32_t tsdbGetOrCreateMemData(SMemTable *pMemTable, tb_uid_t suid, tb_uid_t uid, SMemData **ppMemData);
 static int     memDataPCmprFn(const void *p1, const void *p2);
 static int32_t tPutTSDBRow(uint8_t *p, TSDBROW *pRow);
@@ -224,7 +220,7 @@ static int32_t tsdbGetOrCreateMemData(SMemTable *pMemTable, tb_uid_t suid, tb_ui
   }
 
   // create
-  pMemData = vnodeBufPoolMalloc(pPool, sizeof(*pMemData) + SL_NODE_HALF_SIZE(maxLevel) * 2);
+  pMemData = vnodeBufPoolMalloc(pPool, sizeof(*pMemData) + SL_NODE_SIZE(maxLevel) * 2);
   if (pMemData == NULL) {
     code = TSDB_CODE_OUT_OF_MEMORY;
     goto _err;
@@ -239,11 +235,15 @@ static int32_t tsdbGetOrCreateMemData(SMemTable *pMemTable, tb_uid_t suid, tb_ui
   pMemData->sl.maxLevel = maxLevel;
   pMemData->sl.level = 0;
   pMemData->sl.pHead = (SMemSkipListNode *)&pMemData[1];
-  pMemData->sl.pTail = (SMemSkipListNode *)POINTER_SHIFT(pMemData->sl.pHead, SL_NODE_HALF_SIZE(maxLevel));
+  pMemData->sl.pTail = (SMemSkipListNode *)POINTER_SHIFT(pMemData->sl.pHead, SL_NODE_SIZE(maxLevel));
+  pMemData->sl.pHead->level = maxLevel;
+  pMemData->sl.pTail->level = maxLevel;
 
   for (int8_t iLevel = 0; iLevel < pMemData->sl.maxLevel; iLevel++) {
-    SL_HEAD_FORWARD(&pMemData->sl, iLevel) = pMemData->sl.pTail;
-    SL_TAIL_BACKWARD(&pMemData->sl, iLevel) = pMemData->sl.pHead;
+    SL_NODE_FORWARD(pMemData->sl.pHead, iLevel) = pMemData->sl.pTail;
+    SL_NODE_BACKWARD(pMemData->sl.pHead, iLevel) = NULL;
+    SL_NODE_BACKWARD(pMemData->sl.pTail, iLevel) = pMemData->sl.pHead;
+    SL_NODE_FORWARD(pMemData->sl.pTail, iLevel) = NULL;
   }
 
   if (idx < 0) idx = 0;
@@ -315,30 +315,12 @@ static void memDataMovePos(SMemData *pMemData, TSDBROW *pRow, int8_t isForward,
   int      c;
 
   if (isForward) {
-    for (int8_t iLevel = pMemData->sl.maxLevel - 1; iLevel >= 0; iLevel--) {
-      if (iLevel < pMemData->sl.level) {
-        SMemSkipListNode *px = pos[iLevel];
-        SMemSkipListNode *p = SL_NODE_FORWARD(px, iLevel);
-
-        while (p != pMemData->sl.pTail) {
-          pKey = (TSDBKEY *)SL_NODE_DATA(p);
-
-          c = tsdbKeyCmprFn(pKey, pRow);
-          if (c >= 0) {
-            break;
-          } else {
-            px = p;
-            p = SL_NODE_FORWARD(px, iLevel);
-          }
-        }
-
-        pos[iLevel] = px;
-      }
-    }
+    // TODO
   } else {
+    SMemSkipListNode *px = pMemData->sl.pTail;
+
     for (int8_t iLevel = pMemData->sl.maxLevel - 1; iLevel >= 0; iLevel--) {
       if (iLevel < pMemData->sl.level) {
-        SMemSkipListNode *px = pos[iLevel];
         SMemSkipListNode *p = SL_NODE_BACKWARD(px, iLevel);
 
         while (p != pMemData->sl.pHead) {
@@ -359,6 +341,36 @@ static void memDataMovePos(SMemData *pMemData, TSDBROW *pRow, int8_t isForward,
   }
 }
 
+static void memMovePosFrom(SMemData *pMemData, SMemSkipListNode *pNode, TSDBROW *pRow, int8_t isForward,
+                           SMemSkipListNode **pos) {
+  SMemSkipListNode *px = pNode;
+  TSDBKEY          *pKey;
+  SMemSkipListNode *p;
+  int               c;
+
+  if (isForward) {
+  } else {
+    ASSERT(pNode != pMemData->sl.pHead);
+
+    for (int8_t iLevel = pMemData->sl.maxLevel - 1; iLevel >= 0; iLevel--) {
+      p = SL_NODE_BACKWARD(px, iLevel);
+      while (p != pMemData->sl.pHead) {
+        pKey = (TSDBKEY *)SL_NODE_DATA(p);
+
+        c = tsdbKeyCmprFn(pKey, pRow);
+        if (c <= 0) {
+          break;
+        } else {
+          px = p;
+          p = SL_NODE_BACKWARD(px, iLevel);
+        }
+      }
+
+      pos[iLevel] = px;
+    }
+  }
+}
+
 static int32_t memDataPutRow(SVBufPool *pPool, SMemData *pMemData, TSDBROW *pRow, int8_t isForward,
                              SMemSkipListNode **pos) {
   int32_t           code = 0;
@@ -381,128 +393,4 @@ static int32_t memDataPutRow(SVBufPool *pPool, SMemData *pMemData, TSDBROW *pRow
 
 _exit:
   return code;
-}
-
-#if 0  //====================================================================================
-
-
-// SMemTable ========================
-int32_t tsdbInsertData2(SMemTable *pMemTb, int64_t version, const SVSubmitBlk *pSubmitBlk) {
-  SMemData  *pMemData;
-  STsdb     *pTsdb = pMemTb->pTsdb;
-  SVnode    *pVnode = pTsdb->pVnode;
-  SVBufPool *pPool = pVnode->inUse;
-  tb_uid_t   suid = pSubmitBlk->suid;
-  tb_uid_t   uid = pSubmitBlk->uid;
-  int32_t    iBucket;
-
-  // search SMemData by hash
-  iBucket = HASH_BUCKET(suid, uid, pMemTb->nBucket);
-  for (pMemData = pMemTb->pBuckets[iBucket]; pMemData; pMemData = pMemData->pHashNext) {
-    if (pMemData->suid == suid && pMemData->uid == uid) break;
-  }
-
-  // create pMemData if need
-  if (pMemData == NULL) {
-    int8_t            maxLevel = pVnode->config.tsdbCfg.slLevel;
-    int32_t           tsize = sizeof(*pMemData) + SL_NODE_HALF_SIZE(maxLevel) * 2;
-    SMemSkipListNode *pHead, *pTail;
-
-    pMemData = vnodeBufPoolMalloc(pPool, tsize);
-    if (pMemData == NULL) {
-      terrno = TSDB_CODE_OUT_OF_MEMORY;
-      return -1;
-    }
-
-    pMemData->pHashNext = NULL;
-    pMemData->suid = suid;
-    pMemData->uid = uid;
-    pMemData->minKey = TSKEY_MAX;
-    pMemData->maxKey = TSKEY_MIN;
-    pMemData->minVer = -1;
-    pMemData->maxVer = -1;
-    pMemData->nRows = 0;
-    pMemData->sl.seed = taosRand();
-    pMemData->sl.maxLevel = maxLevel;
-    pMemData->sl.level = 0;
-    pMemData->sl.size = 0;
-    pHead = SL_HEAD_NODE(&pMemData->sl);
-    pTail = SL_TAIL_NODE(&pMemData->sl);
-    pHead->level = maxLevel;
-    pTail->level = maxLevel;
-    for (int iLevel = 0; iLevel < maxLevel; iLevel++) {
-      SL_HEAD_NODE_FORWARD(pHead, iLevel) = pTail;
-      SL_TAIL_NODE_BACKWARD(pTail, iLevel) = pHead;
-    }
-
-    // add to hash
-    if (pMemTb->nHash >= pMemTb->nBucket) {
-      // rehash (todo)
-    }
-    iBucket = HASH_BUCKET(suid, uid, pMemTb->nBucket);
-    pMemData->pHashNext = pMemTb->pBuckets[iBucket];
-    pMemTb->pBuckets[iBucket] = pMemData;
-    pMemTb->nHash++;
-
-    // sort organize (todo)
-  }
-
-  // do insert data to SMemData
-  SMemSkipListNode *forwards[SL_MAX_LEVEL];
-  SMemSkipListNode *pNode;
-  int32_t           iRow;
-  STsdbRow          tRow = {.version = version};
-  SEncoder          ec = {0};
-  SDecoder          dc = {0};
-
-  tDecoderInit(&dc, pSubmitBlk->pData, pSubmitBlk->nData);
-  tsdbMemSkipListCursorInit(pMemTb->pSlc, &pMemData->sl);
-  for (iRow = 0;; iRow++) {
-    if (tDecodeIsEnd(&dc)) break;
-
-    // decode row
-    if (tDecodeBinary(&dc, (uint8_t **)&tRow.pRow, &tRow.szRow) < 0) {
-      terrno = TSDB_CODE_INVALID_MSG;
-      return -1;
-    }
-
-    // move cursor
-    tsdbMemSkipListCursorMoveTo(pMemTb->pSlc, version, tRow.pRow->ts, 0);
-
-    // encode row
-    pNode = tsdbMemSkipListNodeCreate(pPool, &pMemData->sl, &tRow);
-    if (pNode == NULL) {
-      terrno = TSDB_CODE_OUT_OF_MEMORY;
-      return -1;
-    }
-
-    // put the node
-    tsdbMemSkipListCursorPut(pMemTb->pSlc, pNode);
-
-    // update status
-    if (tRow.pRow->ts < pMemData->minKey) pMemData->minKey = tRow.pRow->ts;
-    if (tRow.pRow->ts > pMemData->maxKey) pMemData->maxKey = tRow.pRow->ts;
-  }
-  tDecoderClear(&dc);
-
-  // update status
-  if (pMemData->minVer == -1) pMemData->minVer = version;
-  if (pMemData->maxVer == -1 || pMemData->maxVer < version) pMemData->maxVer = version;
-
-  if (pMemTb->minKey < pMemData->minKey) pMemTb->minKey = pMemData->minKey;
-  if (pMemTb->maxKey < pMemData->maxKey) pMemTb->maxKey = pMemData->maxKey;
-  if (pMemTb->minVer == -1) pMemTb->minVer = version;
-  if (pMemTb->maxVer == -1 || pMemTb->maxVer < version) pMemTb->maxVer = version;
-
-  return 0;
-}
-
-static void tsdbMemSkipListCursorInit(SMemSkipListCurosr *pSlc, SMemSkipList *pSl) {
-  SMemSkipListNode *pHead = SL_HEAD_NODE(pSl);
-  pSlc->pSl = pSl;
-  // for (int8_t iLevel = 0; iLevel < pSl->maxLevel; iLevel++) {
-  //   pSlc->forwards[iLevel] = pHead;
-  // }
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file