diff --git a/src/common/inc/dataformat.h b/src/common/inc/dataformat.h
index 08e49dd3c5c6045e074baeac38cac0c99e3b4ded..4589a0573aca0e9a8595cb9942f6ddfc9b6bc00b 100644
--- a/src/common/inc/dataformat.h
+++ b/src/common/inc/dataformat.h
@@ -69,31 +69,35 @@ void      tdUpdateSchema(STSchema *pSchema);
 // ----------------- Data row structure
 
 /* A data row, the format is like below:
- * +---------+---------------------------------+
- * | int32_t |                                 |
- * +---------+---------------------------------+
- * |   len   |                row              |
- * +---------+---------------------------------+
+ * +----------+---------+---------------------------------+---------------------------------+
+ * | int32_t  | int32_t |                                 |                                 |
+ * +----------+---------+---------------------------------+---------------------------------+
+ * |   len    |  flen   |           First part            |             Second part         |
+ * +----------+---------+---------------------------------+---------------------------------+
+ * plen: first part length
  * len: the length including sizeof(row) + sizeof(len)
  * row: actual row data encoding
  */
 typedef void *SDataRow;
 
-#define TD_DATA_ROW_HEAD_SIZE sizeof(int32_t)
+#define TD_DATA_ROW_HEAD_SIZE (2 * sizeof(int32_t))
 
 #define dataRowLen(r) (*(int32_t *)(r))
+#define dataRowFLen(r) (*(int32_t *)((char *)(r) + sizeof(int32_t)))
 #define dataRowTuple(r) ((char *)(r) + TD_DATA_ROW_HEAD_SIZE)
 #define dataRowSetLen(r, l) (dataRowLen(r) = (l))
+#define dataRowSetFLen(r, l) (dataRowFLen(r) = (l))
 #define dataRowIdx(r, i) ((char *)(r) + i)
 #define dataRowCpy(dst, r) memcpy((dst), (r), dataRowLen(r))
+#define dataRowAt(r, idx) ((char *)(r) + (idx))
 
-SDataRow tdNewDataRow(int32_t bytes);
+void     tdInitDataRow(SDataRow row, STSchema *pSchema);
 int      tdMaxRowBytesFromSchema(STSchema *pSchema);
+SDataRow tdNewDataRow(int32_t bytes, STSchema *pSchema);
 SDataRow tdNewDataRowFromSchema(STSchema *pSchema);
 void     tdFreeDataRow(SDataRow row);
-int      tdAppendColVal(SDataRow row, void *value, STColumn *pCol, int32_t suffixOffset);
-void     tdDataRowCpy(void *dst, SDataRow row);
-void     tdDataRowReset(SDataRow row);
+int      tdAppendColVal(SDataRow row, void *value, STColumn *pCol);
+void     tdDataRowReset(SDataRow row, STSchema *pSchema);
 SDataRow tdDataRowDup(SDataRow row);
 
 /* Data rows definition, the format of it is like below:
diff --git a/src/common/src/dataformat.c b/src/common/src/dataformat.c
index c6fd4af28428ac0d7264922be915f5ad3d0016c8..58530c5e3d54bdefe7a38b9e6c9c13112f0a2602 100644
--- a/src/common/src/dataformat.c
+++ b/src/common/src/dataformat.c
@@ -14,6 +14,8 @@
  */
 #include "dataformat.h"
 
+static int tdFLenFromSchema(STSchema *pSchema);
+
 /**
  * Create a new STColumn object
  * ASSUMPTIONS: VALID PARAMETERS
@@ -157,6 +159,14 @@ void tdUpdateSchema(STSchema *pSchema) {
   }
 }
 
+/**
+ * Initialize a data row
+ */
+void tdInitDataRow(SDataRow row, STSchema *pSchema) {
+  dataRowSetFLen(row, TD_DATA_ROW_HEAD_SIZE);
+  dataRowSetLen(row, TD_DATA_ROW_HEAD_SIZE + tdFLenFromSchema(pSchema));
+}
+
 /**
  * Create a data row with maximum row length bytes.
  *
@@ -167,13 +177,13 @@ void tdUpdateSchema(STSchema *pSchema) {
  * @return SDataRow object for success
  *         NULL for failure
  */
-SDataRow tdNewDataRow(int32_t bytes) {
+SDataRow tdNewDataRow(int32_t bytes, STSchema *pSchema) {
   int32_t size = sizeof(int32_t) + bytes;
 
   SDataRow row = malloc(size);
   if (row == NULL) return NULL;
 
-  dataRowSetLen(row, sizeof(int32_t));
+  tdInitDataRow(row, pSchema);
 
   return row;
 }
@@ -197,14 +207,7 @@ int tdMaxRowBytesFromSchema(STSchema *pSchema) {
   return bytes;
 }
 
-SDataRow tdNewDataRowFromSchema(STSchema *pSchema) {
-  int bytes = 0;
-  {
-    // TODO: estimiate size from schema
-  }
-
-  return tdNewDataRow(bytes);
-}
+SDataRow tdNewDataRowFromSchema(STSchema *pSchema) { return tdNewDataRow(tdMaxRowBytesFromSchema(pSchema), pSchema); }
 
 /**
  * Free the SDataRow object
@@ -214,62 +217,37 @@ void tdFreeDataRow(SDataRow row) {
 }
 
 /**
- * Append a column value to a SDataRow object.
- * NOTE: THE APPLICATION SHOULD MAKE SURE VALID PARAMETERS. THE FUNCTION ASSUMES
- * THE ROW OBJECT HAS ENOUGH SPACE TO HOLD THE VALUE.
- *
- * @param row the row to append value to
- * @param value value pointer to append
- * @param pSchema schema
- * @param colIdx column index
- * 
- * @return 0 for success and -1 for failure
+ * Append a column value to the data row
  */
-// int32_t tdAppendColVal(SDataRow row, void *value, SColumn *pCol, int32_t suffixOffset) {
-//   int32_t offset;
-
-//   switch (pCol->type) {
-//     case TD_DATATYPE_BOOL:
-//     case TD_DATATYPE_TINYINT:
-//     case TD_DATATYPE_SMALLINT:
-//     case TD_DATATYPE_INT:
-//     case TD_DATATYPE_BIGINT:
-//     case TD_DATATYPE_FLOAT:
-//     case TD_DATATYPE_DOUBLE:
-//     case TD_DATATYPE_TIMESTAMP:
-//       memcpy(dataRowIdx(row, pCol->offset + sizeof(int32_t)), value, rowDataLen[pCol->type]);
-//       if (dataRowLen(row) < suffixOffset + sizeof(int32_t))
-//         dataRowSetLen(row, dataRowLen(row) + rowDataLen[pCol->type]);
-//       break;
-//     case TD_DATATYPE_VARCHAR:
-//       offset = dataRowLen(row) > suffixOffset ? dataRowLen(row) : suffixOffset;
-//       memcpy(dataRowIdx(row, pCol->offset+sizeof(int32_t)), (void *)(&offset), sizeof(offset));
-//     case TD_DATATYPE_NCHAR:
-//     case TD_DATATYPE_BINARY:
-//       break;
-//     default:
-//       return -1;
-//   }
-
-//   return 0;
-// }
+int tdAppendColVal(SDataRow row, void *value, STColumn *pCol) {
+  switch (colType(pCol))
+  {
+  case TSDB_DATA_TYPE_BINARY:
+  case TSDB_DATA_TYPE_NCHAR:
+    *(int32_t *)dataRowAt(row, dataRowFLen(row)) = dataRowLen(row);
+    dataRowFLen(row) += TYPE_BYTES[colType(pCol)];
+    memcpy((void *)dataRowAt(row, dataRowLen(row)), value, strlen(value));
+    dataRowLen(row) += strlen(value);
+    break;
+  default:
+    memcpy(dataRowAt(row, dataRowFLen(row)), value, TYPE_BYTES[colType(pCol)]);
+    dataRowFLen(row) += TYPE_BYTES[colType(pCol)];
+    break;
+  }
+}
+
+void tdDataRowReset(SDataRow row, STSchema *pSchema) { tdInitDataRow(row, pSchema); }
 
-/**
- * Copy a data row to a destination
- * ASSUMPTIONS: dst has enough room for a copy of row
- */
-void tdDataRowCpy(void *dst, SDataRow row) { memcpy(dst, row, dataRowLen(row)); }
-void tdDataRowReset(SDataRow row) { dataRowSetLen(row, sizeof(int32_t)); }
 SDataRow tdDataRowDup(SDataRow row) {
-  SDataRow trow = tdNewDataRow(dataRowLen(row));
+  SDataRow trow = malloc(dataRowLen(row));
   if (trow == NULL) return NULL;
 
   dataRowCpy(trow, row);
-  return row;
+  return trow;
 }
 
 void tdDataRowsAppendRow(SDataRows rows, SDataRow row) {
-  tdDataRowCpy((void *)((char *)rows + dataRowsLen(rows)), row);
+  dataRowCpy((void *)((char *)rows + dataRowsLen(rows)), row);
   dataRowsSetLen(rows, dataRowsLen(rows) + dataRowLen(row));
 }
 
@@ -300,4 +278,17 @@ SDataRow tdDataRowsNext(SDataRowsIter *pIter) {
   }
 
   return row;
+}
+
+/**
+ * Return the first part length of a data row for a schema
+ */
+static int tdFLenFromSchema(STSchema *pSchema) {
+  int ret = 0;
+  for (int i = 0; i < schemaNCols(pSchema); i++) {
+    STColumn *pCol = schemaColAt(pSchema, i);
+    ret += TYPE_BYTES[pCol->type];
+  }
+
+  return ret;
 }
\ No newline at end of file
diff --git a/src/vnode/tsdb/inc/tsdb.h b/src/vnode/tsdb/inc/tsdb.h
index c41384114abd7eb039fd8c4ad0e442eaf92c8ec1..57798b6a091401d2eb644b4337612428032b7ea6 100644
--- a/src/vnode/tsdb/inc/tsdb.h
+++ b/src/vnode/tsdb/inc/tsdb.h
@@ -96,7 +96,7 @@ typedef struct {
   STableId tableId;
   int32_t  padding;    // TODO just for padding here
   int32_t  sversion;   // data schema version
-  int32_t  len;        // message length
+  int32_t  len;        // data part length, not including the SSubmitBlk head
   char     data[];
 } SSubmitBlk;
 
diff --git a/src/vnode/tsdb/src/tsdbMain.c b/src/vnode/tsdb/src/tsdbMain.c
index 37901ba588b91b535b0ec1734e6f393f8afa20de..f3aed75e790c3aba4e3baf73bfece7eab5a97095 100644
--- a/src/vnode/tsdb/src/tsdbMain.c
+++ b/src/vnode/tsdb/src/tsdbMain.c
@@ -621,7 +621,7 @@ static int32_t tdInsertRowToTable(STsdbRepo *pRepo, SDataRow row, STable *pTable
   }
 
   pNode->level = level;
-  tdDataRowCpy(SL_GET_NODE_DATA(pNode), row);
+  dataRowCpy(SL_GET_NODE_DATA(pNode), row);
 
   // Insert the skiplist node into the data
   tsdbInsertRowToTableImpl(pNode, pTable);
diff --git a/src/vnode/tsdb/tests/tsdbTests.cpp b/src/vnode/tsdb/tests/tsdbTests.cpp
index 1aa85c0808db26afb87a45536b3211365fe24ed0..eba7df3adb351adb137ef84576f8f2081a9b320c 100644
--- a/src/vnode/tsdb/tests/tsdbTests.cpp
+++ b/src/vnode/tsdb/tests/tsdbTests.cpp
@@ -32,15 +32,29 @@ TEST(TsdbTest, createRepo) {
 
   tsdbCreateTable(pRepo, &tCfg);
 
-  // 3. Loop to write some simple data
-  // int         size = tdMaxRowBytesFromSchema(schema);
-  // int         nrows = 100;
-  // SSubmitMsg *pMsg = (SSubmitMsg *)malloc(sizeof(SSubmitMsg) + sizeof(SSubmitBlk+ size * nrows);
-
-  // {
-  //   // TODO
+  // // 3. Loop to write some simple data
+  // int nRows = 10;
+  // SSubmitMsg *pMsg = (SSubmitMsg *)malloc(sizeof(SSubmitMsg) + sizeof(SSubmitBlk) + tdMaxRowBytesFromSchema(schema) * nRows);
+
+  // SSubmitBlk *pBlock = pMsg->blocks;
+  // pBlock->tableId = {.uid = 987607499877672L, .tid = 0};
+  // pBlock->sversion = 0;
+  // pBlock->len = 0;
+  // int64_t start_time = 1584081000000;
+  // for (int i = 0; i < nRows; i++) {
+  //   int64_t ttime = start_time + 1000 * i;
+  //   SDataRow row = (SDataRow)(pBlock->data + pBlock->len);
+  //   dataRowInit(row);
+
+  //   for (int j; j < schemaNCols(schema); j++) {
+  //     if (j == 0) { // Just for timestamp
+  //       tdAppendColVal(row, (void *)(&time), schemaColAt(schema, i), );
+  //     } else { // For int
+
+  //     }
+  //   }
+
+  //   pBlock->len += dataRowLen(row);
   // }
-
-  // tsdbInsertData(pRepo, pMsg);
 }