diff --git a/include/common/tmsg.h b/include/common/tmsg.h
index 9d001c95347dc9e367ab79affd6764d3a79e1f8b..5ca6a337a8aecbc03e04e45673b4b689aa872289 100644
--- a/include/common/tmsg.h
+++ b/include/common/tmsg.h
@@ -296,13 +296,13 @@ void    tFreeSSubmitRsp(SSubmitRsp* pRsp);
 #define COL_IDX_ON   ((int8_t)0x2)
 #define COL_SET_NULL ((int8_t)0x10)
 #define COL_SET_VAL  ((int8_t)0x20)
-typedef struct SSchema {
+struct SSchema {
   int8_t   type;
   int8_t   flags;
   col_id_t colId;
   int32_t  bytes;
   char     name[TSDB_COL_NAME_LEN];
-} SSchema;
+};
 
 #define COL_IS_SET(FLG)  (((FLG) & (COL_SET_VAL | COL_SET_NULL)) != 0)
 #define COL_CLR_SET(FLG) ((FLG) &= (~(COL_SET_VAL | COL_SET_NULL)))
@@ -648,7 +648,7 @@ typedef struct {
   };
   bool output;  // TODO remove it later
 
-  int16_t type;
+  int8_t  type;
   int32_t bytes;
   uint8_t precision;
   uint8_t scale;
diff --git a/source/client/src/clientImpl.c b/source/client/src/clientImpl.c
index 8357e2d627858b638e362d2bf908af27bd5b0cc5..480fd99c81b7e30309745c97f5df3e19e8054cf9 100644
--- a/source/client/src/clientImpl.c
+++ b/source/client/src/clientImpl.c
@@ -1762,6 +1762,10 @@ int32_t setResultDataPtr(SReqResultInfo* pResultInfo, TAOS_FIELD* pFields, int32
 
   char* p = (char*)pResultInfo->pData;
 
+  // version:
+  int32_t blockVersion = *(int32_t*)p;
+  p += sizeof(int32_t);
+
   int32_t dataLen = *(int32_t*)p;
   p += sizeof(int32_t);
 
@@ -1782,7 +1786,7 @@ int32_t setResultDataPtr(SReqResultInfo* pResultInfo, TAOS_FIELD* pFields, int32
   // check fields
   for (int32_t i = 0; i < numOfCols; ++i) {
     int16_t type = *(int16_t*)p;
-    p += sizeof(int16_t);
+    p += sizeof(int8_t);
 
     int32_t bytes = *(int32_t*)p;
     p += sizeof(int32_t);
diff --git a/source/common/src/tdatablock.c b/source/common/src/tdatablock.c
index bcbdf8d78689bda6f4c12f5e7a2f52e59aef5ca4..45bbe969238e3e31927522cf1ce43780e88e177b 100644
--- a/source/common/src/tdatablock.c
+++ b/source/common/src/tdatablock.c
@@ -676,9 +676,9 @@ size_t blockDataGetRowSize(SSDataBlock* pBlock) {
  * @return
  */
 size_t blockDataGetSerialMetaSize(uint32_t numOfCols) {
-  // | total length | total rows | total columns | has column seg| block group id | column schema | each column length |
-  return sizeof(int32_t) + sizeof(int32_t) + sizeof(int32_t) + sizeof(int32_t) + sizeof(uint64_t) +
-         numOfCols * (sizeof(int16_t) + sizeof(int32_t)) + numOfCols * sizeof(int32_t);
+  // | version | total length | total rows | total columns | flag seg| block group id | column schema | each column length |
+  return sizeof(int32_t) + sizeof(int32_t) + sizeof(int32_t) + sizeof(int32_t) + sizeof(int32_t) + sizeof(uint64_t) +
+         numOfCols * (sizeof(int8_t) + sizeof(int32_t)) + numOfCols * sizeof(int32_t);
 }
 
 double blockDataGetSerialRowSize(const SSDataBlock* pBlock) {
@@ -1582,7 +1582,7 @@ int32_t tEncodeDataBlock(void** buf, const SSDataBlock* pBlock) {
   for (int32_t i = 0; i < sz; i++) {
     SColumnInfoData* pColData = (SColumnInfoData*)taosArrayGet(pBlock->pDataBlock, i);
     tlen += taosEncodeFixedI16(buf, pColData->info.colId);
-    tlen += taosEncodeFixedI16(buf, pColData->info.type);
+    tlen += taosEncodeFixedI8(buf, pColData->info.type);
     tlen += taosEncodeFixedI32(buf, pColData->info.bytes);
     tlen += taosEncodeFixedBool(buf, pColData->hasNull);
 
@@ -1614,7 +1614,7 @@ void* tDecodeDataBlock(const void* buf, SSDataBlock* pBlock) {
   for (int32_t i = 0; i < sz; i++) {
     SColumnInfoData data = {0};
     buf = taosDecodeFixedI16(buf, &data.info.colId);
-    buf = taosDecodeFixedI16(buf, &data.info.type);
+    buf = taosDecodeFixedI8(buf, &data.info.type);
     buf = taosDecodeFixedI32(buf, &data.info.bytes);
     buf = taosDecodeFixedBool(buf, &data.hasNull);
 
@@ -2074,6 +2074,10 @@ char* buildCtbNameByGroupId(const char* stbName, uint64_t groupId) {
 
 void blockEncode(const SSDataBlock* pBlock, char* data, int32_t* dataLen, int32_t numOfCols, int8_t needCompress) {
   // todo extract method
+  int32_t* version = (int32_t*)data;
+  *version = 1;
+  data += sizeof(int32_t);
+
   int32_t* actualLen = (int32_t*)data;
   data += sizeof(int32_t);
 
@@ -2085,8 +2089,11 @@ void blockEncode(const SSDataBlock* pBlock, char* data, int32_t* dataLen, int32_
   *cols = numOfCols;
   data += sizeof(int32_t);
 
-  int32_t* hasColumnSegment = (int32_t*)data;
-  *hasColumnSegment = 1;
+  // flag segment.
+  // the inital bit is for column info
+  int32_t* flagSegment = (int32_t*)data;
+  *flagSegment = (1<<31);
+
   data += sizeof(int32_t);
 
   uint64_t* groupId = (uint64_t*)data;
@@ -2095,8 +2102,8 @@ void blockEncode(const SSDataBlock* pBlock, char* data, int32_t* dataLen, int32_
   for (int32_t i = 0; i < numOfCols; ++i) {
     SColumnInfoData* pColInfoData = taosArrayGet(pBlock->pDataBlock, i);
 
-    *((int16_t*)data) = pColInfoData->info.type;
-    data += sizeof(int16_t);
+    *((int8_t*)data) = pColInfoData->info.type;
+    data += sizeof(int8_t);
 
     *((int32_t*)data) = pColInfoData->info.bytes;
     data += sizeof(int32_t);
@@ -2145,6 +2152,10 @@ void blockEncode(const SSDataBlock* pBlock, char* data, int32_t* dataLen, int32_
 const char* blockDecode(SSDataBlock* pBlock, const char* pData) {
   const char* pStart = pData;
 
+  int32_t version = *(int32_t*) pStart;
+  pStart += sizeof(int32_t);
+  ASSERT(version == 1);
+
   // total length sizeof(int32_t)
   int32_t dataLen = *(int32_t*)pStart;
   pStart += sizeof(int32_t);
@@ -2158,7 +2169,8 @@ const char* blockDecode(SSDataBlock* pBlock, const char* pData) {
   pStart += sizeof(int32_t);
 
   // has column info segment
-  int32_t hasColumnInfo = *(int32_t*)pStart;
+  int32_t flagSeg = *(int32_t*)pStart;
+  int32_t hasColumnInfo = (flagSeg >> 31);
   pStart += sizeof(int32_t);
 
   // group id sizeof(uint64_t)
@@ -2173,7 +2185,7 @@ const char* blockDecode(SSDataBlock* pBlock, const char* pData) {
   for (int32_t i = 0; i < numOfCols; ++i) {
     SColumnInfoData* pColInfoData = taosArrayGet(pBlock->pDataBlock, i);
     pColInfoData->info.type = *(int16_t*)pStart;
-    pStart += sizeof(int16_t);
+    pStart += sizeof(int8_t);
 
     pColInfoData->info.bytes = *(int32_t*)pStart;
     pStart += sizeof(int32_t);
diff --git a/source/libs/executor/src/executorimpl.c b/source/libs/executor/src/executorimpl.c
index 752b93bcea000d45efd3d632eaa4ac27bd156be9..b7e099d0b1127a61c5cd6d7bfb04777200773b4b 100644
--- a/source/libs/executor/src/executorimpl.c
+++ b/source/libs/executor/src/executorimpl.c
@@ -4071,7 +4071,11 @@ SOperatorInfo* createOperatorTree(SPhysiNode* pPhyNode, SExecTaskInfo* pTaskInfo
     } else {
       ASSERT(0);
     }
-    pOperator->resultDataBlockId = pPhyNode->pOutputDataBlockDesc->dataBlockId;
+
+    if (pOperator != NULL) {
+      pOperator->resultDataBlockId = pPhyNode->pOutputDataBlockDesc->dataBlockId;
+    }
+
     return pOperator;
   }