diff --git a/include/common/tmsg.h b/include/common/tmsg.h
index c641fbb1a3b2c4ff877179dc10a9e50f7df76d48..8a17d9d710d29513cadf4ecac470a72a14c4629e 100644
--- a/include/common/tmsg.h
+++ b/include/common/tmsg.h
@@ -265,7 +265,8 @@ typedef struct {
 typedef struct {
   char    name[TSDB_TABLE_FNAME_LEN];
   int8_t  alterType;
-  SSchema schema;
+  int32_t numOfColumns;
+  SSchema pSchema[];
 } SMAlterStbReq;
 
 typedef struct {
diff --git a/source/dnode/mnode/impl/inc/mndDef.h b/source/dnode/mnode/impl/inc/mndDef.h
index e8a9a68466919c0bd77857467e9f859635edb67f..c9228ae78552b3c8ebd663629fe8ee981bf4c1e8 100644
--- a/source/dnode/mnode/impl/inc/mndDef.h
+++ b/source/dnode/mnode/impl/inc/mndDef.h
@@ -301,10 +301,12 @@ typedef struct {
   uint64_t uid;
   uint64_t dbUid;
   int32_t  version;
+  int32_t  nextColId;
   int32_t  numOfColumns;
   int32_t  numOfTags;
+  SSchema* pTags;
+  SSchema* pColumns;
   SRWLatch lock;
-  SSchema* pSchema;
 } SStbObj;
 
 typedef struct {
diff --git a/source/dnode/mnode/impl/src/mndStb.c b/source/dnode/mnode/impl/src/mndStb.c
index 4ccd4b63c44c013150ac99d86acd72cb47824d80..7e025602caa01da422f53bd212088fc13b4f4bdd 100644
--- a/source/dnode/mnode/impl/src/mndStb.c
+++ b/source/dnode/mnode/impl/src/mndStb.c
@@ -84,12 +84,20 @@ static SSdbRaw *mndStbActionEncode(SStbObj *pStb) {
   SDB_SET_INT64(pRaw, dataPos, pStb->uid, STB_ENCODE_OVER)
   SDB_SET_INT64(pRaw, dataPos, pStb->dbUid, STB_ENCODE_OVER)
   SDB_SET_INT32(pRaw, dataPos, pStb->version, STB_ENCODE_OVER)
+  SDB_SET_INT32(pRaw, dataPos, pStb->nextColId, STB_ENCODE_OVER)
   SDB_SET_INT32(pRaw, dataPos, pStb->numOfColumns, STB_ENCODE_OVER)
   SDB_SET_INT32(pRaw, dataPos, pStb->numOfTags, STB_ENCODE_OVER)
 
-  int32_t totalCols = pStb->numOfColumns + pStb->numOfTags;
-  for (int32_t i = 0; i < totalCols; ++i) {
-    SSchema *pSchema = &pStb->pSchema[i];
+  for (int32_t i = 0; i < pStb->numOfColumns; ++i) {
+    SSchema *pSchema = &pStb->pColumns[i];
+    SDB_SET_INT8(pRaw, dataPos, pSchema->type, STB_ENCODE_OVER)
+    SDB_SET_INT32(pRaw, dataPos, pSchema->colId, STB_ENCODE_OVER)
+    SDB_SET_INT32(pRaw, dataPos, pSchema->bytes, STB_ENCODE_OVER)
+    SDB_SET_BINARY(pRaw, dataPos, pSchema->name, TSDB_COL_NAME_LEN, STB_ENCODE_OVER)
+  }
+
+  for (int32_t i = 0; i < pStb->numOfTags; ++i) {
+    SSchema *pSchema = &pStb->pTags[i];
     SDB_SET_INT8(pRaw, dataPos, pSchema->type, STB_ENCODE_OVER)
     SDB_SET_INT32(pRaw, dataPos, pSchema->colId, STB_ENCODE_OVER)
     SDB_SET_INT32(pRaw, dataPos, pSchema->bytes, STB_ENCODE_OVER)
@@ -137,17 +145,26 @@ static SSdbRow *mndStbActionDecode(SSdbRaw *pRaw) {
   SDB_GET_INT64(pRaw, dataPos, &pStb->uid, STB_DECODE_OVER)
   SDB_GET_INT64(pRaw, dataPos, &pStb->dbUid, STB_DECODE_OVER)
   SDB_GET_INT32(pRaw, dataPos, &pStb->version, STB_DECODE_OVER)
+  SDB_GET_INT32(pRaw, dataPos, &pStb->nextColId, STB_DECODE_OVER)
   SDB_GET_INT32(pRaw, dataPos, &pStb->numOfColumns, STB_DECODE_OVER)
   SDB_GET_INT32(pRaw, dataPos, &pStb->numOfTags, STB_DECODE_OVER)
 
-  int32_t totalCols = pStb->numOfColumns + pStb->numOfTags;
-  pStb->pSchema = calloc(totalCols, sizeof(SSchema));
-  if (pStb->pSchema == NULL) {
+  pStb->pColumns = calloc(pStb->numOfColumns, sizeof(SSchema));
+  pStb->pTags = calloc(pStb->numOfTags, sizeof(SSchema));
+  if (pStb->pColumns == NULL || pStb->pTags == NULL) {
     goto STB_DECODE_OVER;
   }
 
-  for (int32_t i = 0; i < totalCols; ++i) {
-    SSchema *pSchema = &pStb->pSchema[i];
+  for (int32_t i = 0; i < pStb->numOfColumns; ++i) {
+    SSchema *pSchema = &pStb->pColumns[i];
+    SDB_GET_INT8(pRaw, dataPos, &pSchema->type, STB_DECODE_OVER)
+    SDB_GET_INT32(pRaw, dataPos, &pSchema->colId, STB_DECODE_OVER)
+    SDB_GET_INT32(pRaw, dataPos, &pSchema->bytes, STB_DECODE_OVER)
+    SDB_GET_BINARY(pRaw, dataPos, pSchema->name, TSDB_COL_NAME_LEN, STB_DECODE_OVER)
+  }
+
+  for (int32_t i = 0; i < pStb->numOfTags; ++i) {
+    SSchema *pSchema = &pStb->pTags[i];
     SDB_GET_INT8(pRaw, dataPos, &pSchema->type, STB_DECODE_OVER)
     SDB_GET_INT32(pRaw, dataPos, &pSchema->colId, STB_DECODE_OVER)
     SDB_GET_INT32(pRaw, dataPos, &pSchema->bytes, STB_DECODE_OVER)
@@ -183,13 +200,24 @@ static int32_t mndStbActionUpdate(SSdb *pSdb, SStbObj *pOld, SStbObj *pNew) {
   mTrace("stb:%s, perform update action, old row:%p new row:%p", pOld->name, pOld, pNew);
 
   taosWLockLatch(&pOld->lock);
-  int32_t totalCols = pNew->numOfTags + pNew->numOfColumns;
-  int32_t totalSize = totalCols * sizeof(SSchema);
-  if (pOld->numOfTags + pOld->numOfColumns < totalCols) {
-    void *pSchema = malloc(totalSize);
+
+  if (pOld->numOfColumns < pNew->numOfColumns) {
+    void *pSchema = malloc(pOld->numOfColumns * sizeof(SSchema));
     if (pSchema != NULL) {
-      free(pOld->pSchema);
-      pOld->pSchema = pSchema;
+      free(pOld->pColumns);
+      pOld->pColumns = pSchema;
+    } else {
+      terrno = TSDB_CODE_OUT_OF_MEMORY;
+      mTrace("stb:%s, failed to perform update action since %s", pOld->name, terrstr());
+      taosWUnLockLatch(&pOld->lock);
+    }
+  }
+
+  if (pOld->numOfTags < pNew->numOfTags) {
+    void *pSchema = malloc(pOld->numOfTags * sizeof(SSchema));
+    if (pSchema != NULL) {
+      free(pOld->pTags);
+      pOld->pTags = pSchema;
     } else {
       terrno = TSDB_CODE_OUT_OF_MEMORY;
       mTrace("stb:%s, failed to perform update action since %s", pOld->name, terrstr());
@@ -199,9 +227,11 @@ static int32_t mndStbActionUpdate(SSdb *pSdb, SStbObj *pOld, SStbObj *pNew) {
 
   pOld->updateTime = pNew->updateTime;
   pOld->version = pNew->version;
+  pOld->nextColId = pNew->nextColId;
   pOld->numOfColumns = pNew->numOfColumns;
   pOld->numOfTags = pNew->numOfTags;
-  memcpy(pOld->pSchema, pNew->pSchema, totalSize);
+  memcpy(pOld->pColumns, pNew->pColumns, pOld->numOfColumns * sizeof(SSchema));
+  memcpy(pOld->pTags, pNew->pTags, pOld->numOfTags * sizeof(SSchema));
   taosWUnLockLatch(&pOld->lock);
   return 0;
 }
@@ -242,9 +272,9 @@ static void *mndBuildCreateStbReq(SMnode *pMnode, SVgObj *pVgroup, SStbObj *pStb
   req.type = TD_SUPER_TABLE;
   req.stbCfg.suid = pStb->uid;
   req.stbCfg.nCols = pStb->numOfColumns;
-  req.stbCfg.pSchema = pStb->pSchema;
+  req.stbCfg.pSchema = pStb->pColumns;
   req.stbCfg.nTagCols = pStb->numOfTags;
-  req.stbCfg.pTagSchema = pStb->pSchema + pStb->numOfColumns;
+  req.stbCfg.pTagSchema = pStb->pTags;
 
   int32_t   contLen = tSerializeSVCreateTbReq(NULL, &req) + sizeof(SMsgHead);
   SMsgHead *pHead = malloc(contLen);
@@ -442,20 +472,32 @@ static int32_t mndCreateStb(SMnode *pMnode, SMnodeMsg *pReq, SMCreateStbReq *pCr
   stbObj.uid = mndGenerateUid(pCreate->name, TSDB_TABLE_FNAME_LEN);
   stbObj.dbUid = pDb->uid;
   stbObj.version = 1;
+  stbObj.nextColId = 1;
   stbObj.numOfColumns = pCreate->numOfColumns;
   stbObj.numOfTags = pCreate->numOfTags;
 
-  int32_t totalCols = stbObj.numOfColumns + stbObj.numOfTags;
-  int32_t totalSize = totalCols * sizeof(SSchema);
-  stbObj.pSchema = malloc(totalSize);
-  if (stbObj.pSchema == NULL) {
+  stbObj.pColumns = malloc(stbObj.numOfColumns * sizeof(SSchema));
+  if (stbObj.pColumns == NULL) {
     terrno = TSDB_CODE_OUT_OF_MEMORY;
     return -1;
   }
-  memcpy(stbObj.pSchema, pCreate->pSchema, totalSize);
+  memcpy(stbObj.pColumns, pCreate->pSchema, stbObj.numOfColumns * sizeof(SSchema));
 
-  for (int32_t i = 0; i < totalCols; ++i) {
-    stbObj.pSchema[i].colId = i + 1;
+  stbObj.pTags = malloc(stbObj.numOfTags * sizeof(SSchema));
+  if (stbObj.pTags == NULL) {
+    terrno = TSDB_CODE_OUT_OF_MEMORY;
+    return -1;
+  }
+  memcpy(stbObj.pTags, pCreate->pSchema + stbObj.numOfColumns, stbObj.numOfTags * sizeof(SSchema));
+
+  for (int32_t i = 0; i < stbObj.numOfColumns; ++i) {
+    stbObj.pColumns[i].colId = stbObj.nextColId;
+    stbObj.nextColId++;
+  }
+
+  for (int32_t i = 0; i < stbObj.numOfTags; ++i) {
+    stbObj.pTags[i].colId = stbObj.nextColId;
+    stbObj.nextColId++;
   }
 
   int32_t code = -1;
@@ -538,25 +580,29 @@ static int32_t mndProcessVCreateStbRsp(SMnodeMsg *pRsp) {
 }
 
 static int32_t mndCheckAlterStbReq(SMAlterStbReq *pAlter) {
-  SSchema *pSchema = &pAlter->schema;
-  pSchema->colId = htonl(pSchema->colId);
-  pSchema->bytes = htonl(pSchema->bytes);
+  pAlter->numOfColumns = htonl(pAlter->numOfColumns);
 
-  if (pSchema->type <= 0) {
-    terrno = TSDB_CODE_MND_INVALID_STB_OPTION;
-    return -1;
-  }
-  if (pSchema->colId < 0 || pSchema->colId >= (TSDB_MAX_COLUMNS + TSDB_MAX_TAGS)) {
-    terrno = TSDB_CODE_MND_INVALID_STB_OPTION;
-    return -1;
-  }
-  if (pSchema->bytes <= 0) {
-    terrno = TSDB_CODE_MND_INVALID_STB_OPTION;
-    return -1;
-  }
-  if (pSchema->name[0] == 0) {
-    terrno = TSDB_CODE_MND_INVALID_STB_OPTION;
-    return -1;
+  for (int32_t i = 0; i < pAlter->numOfColumns; ++i) {
+    SSchema *pSchema = &pAlter->pSchema[i];
+    pSchema->colId = htonl(pSchema->colId);
+    pSchema->bytes = htonl(pSchema->bytes);
+
+    if (pSchema->type <= 0) {
+      terrno = TSDB_CODE_MND_INVALID_STB_OPTION;
+      return -1;
+    }
+    if (pSchema->colId < 0 || pSchema->colId >= (TSDB_MAX_COLUMNS + TSDB_MAX_TAGS)) {
+      terrno = TSDB_CODE_MND_INVALID_STB_OPTION;
+      return -1;
+    }
+    if (pSchema->bytes <= 0) {
+      terrno = TSDB_CODE_MND_INVALID_STB_OPTION;
+      return -1;
+    }
+    if (pSchema->name[0] == 0) {
+      terrno = TSDB_CODE_MND_INVALID_STB_OPTION;
+      return -1;
+    }
   }
 
   return 0;
@@ -769,14 +815,24 @@ static int32_t mndProcessStbMetaReq(SMnodeMsg *pReq) {
   pMeta->suid = htobe64(pStb->uid);
   pMeta->tuid = htobe64(pStb->uid);
 
-  for (int32_t i = 0; i < totalCols; ++i) {
+  for (int32_t i = 0; i < pStb->numOfColumns; ++i) {
     SSchema *pSchema = &pMeta->pSchema[i];
-    SSchema *pSrcSchema = &pStb->pSchema[i];
+    SSchema *pSrcSchema = &pStb->pColumns[i];
+    memcpy(pSchema->name, pSrcSchema->name, TSDB_COL_NAME_LEN);
+    pSchema->type = pSrcSchema->type;
+    pSchema->colId = htonl(pSrcSchema->colId);
+    pSchema->bytes = htonl(pSrcSchema->bytes);
+  }
+
+  for (int32_t i = 0; i < pStb->numOfTags; ++i) {
+    SSchema *pSchema = &pMeta->pSchema[i + pStb->numOfColumns];
+    SSchema *pSrcSchema = &pStb->pTags[i];
     memcpy(pSchema->name, pSrcSchema->name, TSDB_COL_NAME_LEN);
     pSchema->type = pSrcSchema->type;
     pSchema->colId = htonl(pSrcSchema->colId);
     pSchema->bytes = htonl(pSrcSchema->bytes);
   }
+
   taosRUnLockLatch(&pStb->lock);
   mndReleaseDb(pMnode, pDb);
   mndReleaseStb(pMnode, pStb);
@@ -789,11 +845,11 @@ static int32_t mndProcessStbMetaReq(SMnodeMsg *pReq) {
 }
 
 int32_t mndValidateStbInfo(SMnode *pMnode, SSTableMetaVersion *stbs, int32_t num, void **rsp, int32_t *rspLen) {
-  SSdb *pSdb = pMnode->pSdb;
-  int32_t bufSize = num * (sizeof(STableMetaRsp) + 4 * sizeof(SSchema));  
-  void *buf = malloc(bufSize);
-  int32_t len = 0;
-  int32_t contLen = 0;
+  SSdb          *pSdb = pMnode->pSdb;
+  int32_t        bufSize = num * (sizeof(STableMetaRsp) + 4 * sizeof(SSchema));
+  void          *buf = malloc(bufSize);
+  int32_t        len = 0;
+  int32_t        contLen = 0;
   STableMetaRsp *pRsp = NULL;
 
   for (int32_t i = 0; i < num; ++i) {
@@ -803,7 +859,7 @@ int32_t mndValidateStbInfo(SMnode *pMnode, SSTableMetaVersion *stbs, int32_t num
     stb->tversion = ntohs(stb->tversion);
 
     if ((contLen + sizeof(STableMetaRsp)) > bufSize) {
-      bufSize = contLen + (num -i) * (sizeof(STableMetaRsp) + 4 * sizeof(SSchema));
+      bufSize = contLen + (num - i) * (sizeof(STableMetaRsp) + 4 * sizeof(SSchema));
       buf = realloc(buf, bufSize);
     }
 
@@ -812,9 +868,9 @@ int32_t mndValidateStbInfo(SMnode *pMnode, SSTableMetaVersion *stbs, int32_t num
     strcpy(pRsp->dbFName, stb->dbFName);
     strcpy(pRsp->tbName, stb->stbName);
     strcpy(pRsp->stbName, stb->stbName);
-    
+
     mDebug("start to retrieve meta, db:%s, stb:%s", stb->dbFName, stb->stbName);
-    
+
     SDbObj *pDb = mndAcquireDb(pMnode, stb->dbFName);
     if (pDb == NULL) {
       pRsp->numOfColumns = -1;
@@ -826,7 +882,7 @@ int32_t mndValidateStbInfo(SMnode *pMnode, SSTableMetaVersion *stbs, int32_t num
 
     char tbFName[TSDB_TABLE_FNAME_LEN] = {0};
     snprintf(tbFName, sizeof(tbFName), "%s.%s", stb->dbFName, stb->stbName);
-    
+
     SStbObj *pStb = mndAcquireStb(pMnode, tbFName);
     if (pStb == NULL) {
       mndReleaseDb(pMnode, pDb);
@@ -836,7 +892,7 @@ int32_t mndValidateStbInfo(SMnode *pMnode, SSTableMetaVersion *stbs, int32_t num
       mWarn("stb:%s, failed to get meta since %s", tbFName, terrstr());
       continue;
     }
-    
+
     taosRLockLatch(&pStb->lock);
 
     if (stb->suid == pStb->uid && stb->sversion == pStb->version) {
@@ -845,17 +901,17 @@ int32_t mndValidateStbInfo(SMnode *pMnode, SSTableMetaVersion *stbs, int32_t num
       mndReleaseStb(pMnode, pStb);
       continue;
     }
-    
+
     int32_t totalCols = pStb->numOfColumns + pStb->numOfTags;
     int32_t len = totalCols * sizeof(SSchema);
-    
+
     contLen += sizeof(STableMetaRsp) + len;
-    
+
     if (contLen > bufSize) {
-      bufSize = contLen + (num -i - 1) * (sizeof(STableMetaRsp) + 4 * sizeof(SSchema));
+      bufSize = contLen + (num - i - 1) * (sizeof(STableMetaRsp) + 4 * sizeof(SSchema));
       buf = realloc(buf, bufSize);
     }
-    
+
     pRsp->numOfTags = htonl(pStb->numOfTags);
     pRsp->numOfColumns = htonl(pStb->numOfColumns);
     pRsp->precision = pDb->cfg.precision;
@@ -864,15 +920,25 @@ int32_t mndValidateStbInfo(SMnode *pMnode, SSTableMetaVersion *stbs, int32_t num
     pRsp->sversion = htonl(pStb->version);
     pRsp->suid = htobe64(pStb->uid);
     pRsp->tuid = htobe64(pStb->uid);
-    
-    for (int32_t i = 0; i < totalCols; ++i) {
+
+    for (int32_t i = 0; i < pStb->numOfColumns; ++i) {
       SSchema *pSchema = &pRsp->pSchema[i];
-      SSchema *pSrcSchema = &pStb->pSchema[i];
+      SSchema *pSrcSchema = &pStb->pColumns[i];
+      memcpy(pSchema->name, pSrcSchema->name, TSDB_COL_NAME_LEN);
+      pSchema->type = pSrcSchema->type;
+      pSchema->colId = htonl(pSrcSchema->colId);
+      pSchema->bytes = htonl(pSrcSchema->bytes);
+    }
+
+    for (int32_t i = 0; i < pStb->numOfTags; ++i) {
+      SSchema *pSchema = &pRsp->pSchema[i + pStb->numOfColumns];
+      SSchema *pSrcSchema = &pStb->pTags[i];
       memcpy(pSchema->name, pSrcSchema->name, TSDB_COL_NAME_LEN);
       pSchema->type = pSrcSchema->type;
       pSchema->colId = htonl(pSrcSchema->colId);
       pSchema->bytes = htonl(pSrcSchema->bytes);
     }
+
     taosRUnLockLatch(&pStb->lock);
     mndReleaseDb(pMnode, pDb);
     mndReleaseStb(pMnode, pStb);
@@ -890,7 +956,6 @@ int32_t mndValidateStbInfo(SMnode *pMnode, SSTableMetaVersion *stbs, int32_t num
   return 0;
 }
 
-
 static int32_t mndGetNumOfStbs(SMnode *pMnode, char *dbName, int32_t *pNumOfStbs) {
   SSdb *pSdb = pMnode->pSdb;