diff --git a/src/common/inc/tdataformat.h b/src/common/inc/tdataformat.h
index 573836a4e72ddedb0977e2551382edf37ad3adfb..46d13d709409408553c9e99259dad9e7d84c882c 100644
--- a/src/common/inc/tdataformat.h
+++ b/src/common/inc/tdataformat.h
@@ -265,10 +265,11 @@ typedef struct SDataCol {
   TSKEY           ts;         // only used in last NULL column
 } SDataCol;
 
+#define isAllRowsNull(pCol) ((pCol)->len == 0)
 static FORCE_INLINE void dataColReset(SDataCol *pDataCol) { pDataCol->len = 0; }
 
 void dataColInit(SDataCol *pDataCol, STColumn *pCol, void **pBuf, int maxPoints);
-void dataColAppendVal(SDataCol *pCol, void *value, int numOfRows, int maxPoints);
+void dataColAppendVal(SDataCol *pCol, const void *value, int numOfRows, int maxPoints);
 void dataColSetOffset(SDataCol *pCol, int nEle);
 
 bool isNEleNull(SDataCol *pCol, int nEle);
@@ -277,7 +278,10 @@ void dataColSetNEleNull(SDataCol *pCol, int nEle, int maxPoints);
 const void *tdGetNullVal(int8_t type);
 
 // Get the data pointer from a column-wised data
-static FORCE_INLINE void *tdGetColDataOfRow(SDataCol *pCol, int row) {
+static FORCE_INLINE const void *tdGetColDataOfRow(SDataCol *pCol, int row) {
+  if (isAllRowsNull(pCol)) {
+    return tdGetNullVal(pCol->type);
+  }
   if (IS_VAR_DATA_TYPE(pCol->type)) {
     return POINTER_SHIFT(pCol->pData, pCol->dataOff[row]);
   } else {
diff --git a/src/common/src/tdataformat.c b/src/common/src/tdataformat.c
index 2ac6fbe6ddb0ed7ca4d3e6101fbe1e68adc7385c..f26f7511c10e1732722f38808742abd39fc4eef2 100644
--- a/src/common/src/tdataformat.c
+++ b/src/common/src/tdataformat.c
@@ -241,9 +241,21 @@ void dataColInit(SDataCol *pDataCol, STColumn *pCol, void **pBuf, int maxPoints)
   }
 }
 // value from timestamp should be TKEY here instead of TSKEY
-void dataColAppendVal(SDataCol *pCol, void *value, int numOfRows, int maxPoints) {
+void dataColAppendVal(SDataCol *pCol, const void *value, int numOfRows, int maxPoints) {
   ASSERT(pCol != NULL && value != NULL);
 
+  if (isAllRowsNull(pCol)) {
+    if (isNull(value, pCol->type)) {
+      // all null value yet, just return
+      return;
+    }
+
+    if (numOfRows > 0) {
+      // Find the first not null value, fill all previouse values as NULL
+      dataColSetNEleNull(pCol, numOfRows, maxPoints);
+    }
+  }
+
   if (IS_VAR_DATA_TYPE(pCol->type)) {
     // set offset
     pCol->dataOff[numOfRows] = pCol->len;
@@ -440,7 +452,8 @@ static void tdAppendDataRowToDataCol(SDataRow row, STSchema *pSchema, SDataCols
     while (dcol < pCols->numOfCols) {
       SDataCol *pDataCol = &(pCols->cols[dcol]);
       if (rcol >= schemaNCols(pSchema)) {
-        dataColSetNullAt(pDataCol, pCols->numOfRows);
+        // dataColSetNullAt(pDataCol, pCols->numOfRows);
+        dataColAppendVal(pDataCol, tdGetNullVal(pDataCol->type), pCols->numOfRows, pCols->maxPoints);
         dcol++;
         continue;
       }
@@ -454,7 +467,8 @@ static void tdAppendDataRowToDataCol(SDataRow row, STSchema *pSchema, SDataCols
       } else if (pRowCol->colId < pDataCol->colId) {
         rcol++;
       } else {
-        dataColSetNullAt(pDataCol, pCols->numOfRows);
+        // dataColSetNullAt(pDataCol, pCols->numOfRows);
+        dataColAppendVal(pDataCol, tdGetNullVal(pDataCol->type), pCols->numOfRows, pCols->maxPoints);
         dcol++;
       }
     }
@@ -483,7 +497,8 @@ static void tdAppendKvRowToDataCol(SKVRow row, STSchema *pSchema, SDataCols *pCo
     while (dcol < pCols->numOfCols) {
       SDataCol *pDataCol = &(pCols->cols[dcol]);
       if (rcol >= nRowCols || rcol >= schemaNCols(pSchema)) {
-        dataColSetNullAt(pDataCol, pCols->numOfRows);
+        // dataColSetNullAt(pDataCol, pCols->numOfRows);
+        dataColAppendVal(pDataCol, tdGetNullVal(pDataCol->type), pCols->numOfRows, pCols->maxPoints);
         ++dcol;
         continue;
       }
@@ -498,7 +513,8 @@ static void tdAppendKvRowToDataCol(SKVRow row, STSchema *pSchema, SDataCols *pCo
       } else if (colIdx->colId < pDataCol->colId) {
         ++rcol;
       } else {
-        dataColSetNullAt(pDataCol, pCols->numOfRows);
+        // dataColSetNullAt(pDataCol, pCols->numOfRows);
+        dataColAppendVal(pDataCol, tdGetNullVal(pDataCol->type), pCols->numOfRows, pCols->maxPoints);
         ++dcol;
       }
     }
diff --git a/src/tsdb/src/tsdbCommit.c b/src/tsdb/src/tsdbCommit.c
index 8718d5c35a8fdfd4033912c16be9072b75773446..6330da60585afb590ee82018b3204280f62e5f1c 100644
--- a/src/tsdb/src/tsdbCommit.c
+++ b/src/tsdb/src/tsdbCommit.c
@@ -920,7 +920,8 @@ int tsdbWriteBlockImpl(STsdbRepo *pRepo, STable *pTable, SDFile *pDFile, SDataCo
     SDataCol * pDataCol = pDataCols->cols + ncol;
     SBlockCol *pBlockCol = pBlockData->cols + nColsNotAllNull;
 
-    if (isNEleNull(pDataCol, rowsToWrite)) {  // all data to commit are NULL, just ignore it
+    // if (isNEleNull(pDataCol, rowsToWrite)) {  // all data to commit are NULL, just ignore it
+    if (isAllRowsNull(pDataCol)) {  // all data to commit are NULL, just ignore it
       continue;
     }
 
diff --git a/src/tsdb/src/tsdbRead.c b/src/tsdb/src/tsdbRead.c
index 22162da5c6624066cdc3bac01054ac5a44d4e1f7..1a301f49032982f48554f45ea5d4ede1aabf9f48 100644
--- a/src/tsdb/src/tsdbRead.c
+++ b/src/tsdb/src/tsdbRead.c
@@ -1391,7 +1391,7 @@ int32_t doCopyRowsFromFileBlock(STsdbQueryHandle* pQueryHandle, int32_t capacity
 
         // todo refactor, only copy one-by-one
         for (int32_t k = start; k < num + start; ++k) {
-          char* p = tdGetColDataOfRow(src, k);
+          const char* p = tdGetColDataOfRow(src, k);
           memcpy(dst, p, varDataTLen(p));
           dst += bytes;
         }