diff --git a/src/client/inc/tscSQLParser.h b/src/client/inc/tscSQLParser.h
index c7f8ba06e8fc20ea4be57784861ad86b4089aad2..0341b7ed033bb5162131619d803d3885a1dd7a4f 100644
--- a/src/client/inc/tscSQLParser.h
+++ b/src/client/inc/tscSQLParser.h
@@ -20,24 +20,9 @@
 extern "C" {
 #endif
 
-#include "taos.h"
-#include "taosmsg.h"
-#include "ttokendef.h"
-#include "taosdef.h"
-#include "tvariant.h"
-#include "qsqlparser.h"
+#include "tsclient.h"
 
-enum {
-  TSQL_NODE_TYPE_EXPR = 0x1,
-  TSQL_NODE_TYPE_ID = 0x2,
-  TSQL_NODE_TYPE_VALUE = 0x4,
-};
-
-#define NON_ARITHMEIC_EXPR 0
-#define NORMAL_ARITHMETIC 1
-#define AGG_ARIGHTMEIC    2
-
-int32_t tSQLParse(SSqlInfo *pSQLInfo, const char *pSql);
+int32_t tscToSQLCmd(struct SSqlObj* pSql, struct SSqlInfo* pInfo);
 
 #ifdef __cplusplus
 }
diff --git a/src/client/inc/tscSecondaryMerge.h b/src/client/inc/tscSecondaryMerge.h
index 08d995c9f3d789a82f5b8fa1331d8653a017181b..5370d0ec5259c3e47e065d4fe8b37884bdf6a050 100644
--- a/src/client/inc/tscSecondaryMerge.h
+++ b/src/client/inc/tscSecondaryMerge.h
@@ -20,9 +20,9 @@
 extern "C" {
 #endif
 
+#include "qextbuffer.h"
+#include "qinterpolation.h"
 #include "taosmsg.h"
-#include "textbuffer.h"
-#include "tinterpolation.h"
 #include "tlosertree.h"
 #include "tsclient.h"
 
diff --git a/src/client/inc/tscUtil.h b/src/client/inc/tscUtil.h
index a869e45198fe2da615b2178c55a32bcd64a9285a..ef82ac53a2863bb05c361d425b7ddcfc0a3a1f19 100644
--- a/src/client/inc/tscUtil.h
+++ b/src/client/inc/tscUtil.h
@@ -24,10 +24,10 @@ extern "C" {
  * @date   2018/09/30
  */
 #include "os.h"
-#include "textbuffer.h"
+#include "qextbuffer.h"
+#include "taosdef.h"
 #include "tscSecondaryMerge.h"
 #include "tsclient.h"
-#include "taosdef.h"
 
 #define UTIL_METER_IS_SUPERTABLE(metaInfo) \
   (((metaInfo)->pMeterMeta != NULL) && ((metaInfo)->pMeterMeta->tableType == TSDB_TABLE_TYPE_SUPER_TABLE))
@@ -252,6 +252,7 @@ void tscTryQueryNextVnode(SSqlObj *pSql, __async_cb_func_t fp);
 void tscAsyncQuerySingleRowForNextVnode(void *param, TAOS_RES *tres, int numOfRows);
 void tscTryQueryNextClause(SSqlObj* pSql, void (*queryFp)());
 
+int32_t launchMultivnodeInsert(SSqlObj *pSql);
 
 #ifdef __cplusplus
 }
diff --git a/src/client/inc/tsclient.h b/src/client/inc/tsclient.h
index caec0fdbb8c444e865610ac1e08b992decfc31b3..0823e6175fec933f98312138c6a151a53873c6a2 100644
--- a/src/client/inc/tsclient.h
+++ b/src/client/inc/tsclient.h
@@ -32,6 +32,7 @@ extern "C" {
 #include "tutil.h"
 #include "trpc.h"
 #include "qsqltype.h"
+#include "qsqlparser.h"
 
 #define TSC_GET_RESPTR_BASE(res, _queryinfo, col) (res->data + ((_queryinfo)->fieldsInfo.pSqlExpr[col]->offset) * res->numOfRows)
 
@@ -308,14 +309,14 @@ typedef struct _tsc_obj {
   char             sversion[TSDB_VERSION_LEN];
   char             writeAuth : 1;
   char             superAuth : 1;
-  struct _sql_obj *pSql;
-  struct _sql_obj *pHb;
-  struct _sql_obj *sqlList;
+  struct SSqlObj *pSql;
+  struct SSqlObj *pHb;
+  struct SSqlObj *sqlList;
   struct _sstream *streamList;
   pthread_mutex_t  mutex;
 } STscObj;
 
-typedef struct _sql_obj {
+typedef struct SSqlObj {
   void *   signature;
   STscObj *pTscObj;
   void (*fp)();
@@ -340,8 +341,8 @@ typedef struct _sql_obj {
   uint8_t           numOfSubs;
   char *            asyncTblPos;
   void *            pTableHashList;
-  struct _sql_obj **pSubs;
-  struct _sql_obj * prev, *next;
+  struct SSqlObj **pSubs;
+  struct SSqlObj * prev, *next;
 } SSqlObj;
 
 typedef struct _sstream {
@@ -442,9 +443,6 @@ char *tscGetErrorMsgPayload(SSqlCmd *pCmd);
 
 int32_t tscInvalidSQLErrMsg(char *msg, const char *additionalInfo, const char *sql);
 
-// transfer SSqlInfo to SqlCmd struct
-int32_t tscToSQLCmd(SSqlObj *pSql, struct SSqlInfo *pInfo);
-
 void tscQueueAsyncFreeResult(SSqlObj *pSql);
 
 extern void *     pVnodeConn;
@@ -453,7 +451,6 @@ extern void *     tscCacheHandle;
 extern int32_t    globalCode;
 extern int        slaveIndex;
 extern void *     tscTmr;
-extern void *     tscConnCache;
 extern void *     tscQhandle;
 extern int        tscKeepConn[];
 extern int        tsInsertHeadSize;
diff --git a/src/client/src/tscCache.c b/src/client/src/tscCache.c
deleted file mode 100644
index 666d069a58c936e9028b46f9e6244923ac4be993..0000000000000000000000000000000000000000
--- a/src/client/src/tscCache.c
+++ /dev/null
@@ -1,264 +0,0 @@
-/*
- * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
- *
- * This program is free software: you can use, redistribute, and/or modify
- * it under the terms of the GNU Affero General Public License, version 3
- * or later ("AGPL"), as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include "os.h"
-
-#include "tglobalcfg.h"
-#include "tlog.h"
-#include "tmempool.h"
-#include "tsclient.h"
-#include "ttime.h"
-#include "ttimer.h"
-#include "tutil.h"
-
-typedef struct _c_hash_t {
-  uint32_t          ip;
-  uint16_t          port;
-  struct _c_hash_t *prev;
-  struct _c_hash_t *next;
-  void *            data;
-  uint64_t          time;
-} SConnHash;
-
-typedef struct {
-  SConnHash **    connHashList;
-  mpool_h         connHashMemPool;
-  int             maxSessions;
-  int             total;
-  int *           count;
-  int64_t         keepTimer;
-  pthread_mutex_t mutex;
-  void (*cleanFp)(void *);
-  void *tmrCtrl;
-  void *pTimer;
-} SConnCache;
-
-int taosHashConn(void *handle, uint32_t ip, uint16_t port, char *user) {
-  SConnCache *pObj = (SConnCache *)handle;
-  int         hash = 0;
-  // size_t    user_len = strlen(user);
-
-  hash = ip >> 16;
-  hash += (unsigned short)(ip & 0xFFFF);
-  hash += port;
-  while (*user != '\0') {
-    hash += *user;
-    user++;
-  }
-
-  hash = hash % pObj->maxSessions;
-
-  return hash;
-}
-
-void taosRemoveExpiredNodes(SConnCache *pObj, SConnHash *pNode, int hash, uint64_t time) {
-  if (pNode == NULL) return;
-  if (time < pObj->keepTimer + pNode->time) return;
-
-  SConnHash *pPrev = pNode->prev, *pNext;
-
-  while (pNode) {
-    (*pObj->cleanFp)(pNode->data);
-    pNext = pNode->next;
-    pObj->total--;
-    pObj->count[hash]--;
-    tscTrace("%p ip:0x%x:%hu:%d:%p removed, connections in cache:%d", pNode->data, pNode->ip, pNode->port, hash, pNode,
-             pObj->count[hash]);
-    taosMemPoolFree(pObj->connHashMemPool, (char *)pNode);
-    pNode = pNext;
-  }
-
-  if (pPrev)
-    pPrev->next = NULL;
-  else
-    pObj->connHashList[hash] = NULL;
-}
-
-void *taosAddConnIntoCache(void *handle, void *data, uint32_t ip, uint16_t port, char *user) {
-  int         hash;
-  SConnHash * pNode;
-  SConnCache *pObj;
-
-  uint64_t time = taosGetTimestampMs();
-
-  pObj = (SConnCache *)handle;
-  if (pObj == NULL || pObj->maxSessions == 0) return NULL;
-
-  if (data == NULL) {
-    tscTrace("data:%p ip:%p:%d not valid, not added in cache", data, ip, port);
-    return NULL;
-  }
-
-  hash = taosHashConn(pObj, ip, port, user);
-  pNode = (SConnHash *)taosMemPoolMalloc(pObj->connHashMemPool);
-  pNode->ip = ip;
-  pNode->port = port;
-  pNode->data = data;
-  pNode->prev = NULL;
-  pNode->time = time;
-
-  pthread_mutex_lock(&pObj->mutex);
-
-  pNode->next = pObj->connHashList[hash];
-  if (pObj->connHashList[hash] != NULL) (pObj->connHashList[hash])->prev = pNode;
-  pObj->connHashList[hash] = pNode;
-
-  pObj->total++;
-  pObj->count[hash]++;
-  taosRemoveExpiredNodes(pObj, pNode->next, hash, time);
-
-  pthread_mutex_unlock(&pObj->mutex);
-
-  tscTrace("%p ip:0x%x:%hu:%d:%p added, connections in cache:%d", data, ip, port, hash, pNode, pObj->count[hash]);
-
-  return pObj;
-}
-
-void taosCleanConnCache(void *handle, void *tmrId) {
-  int         hash;
-  SConnHash * pNode;
-  SConnCache *pObj;
-
-  pObj = (SConnCache *)handle;
-  if (pObj == NULL || pObj->maxSessions == 0) return;
-  if (pObj->pTimer != tmrId) return;
-
-  uint64_t time = taosGetTimestampMs();
-
-  for (hash = 0; hash < pObj->maxSessions; ++hash) {
-    pthread_mutex_lock(&pObj->mutex);
-    pNode = pObj->connHashList[hash];
-    taosRemoveExpiredNodes(pObj, pNode, hash, time);
-    pthread_mutex_unlock(&pObj->mutex);
-  }
-
-  // tscTrace("timer, total connections in cache:%d", pObj->total);
-  taosTmrReset(taosCleanConnCache, pObj->keepTimer * 2, pObj, pObj->tmrCtrl, &pObj->pTimer);
-}
-
-void *taosGetConnFromCache(void *handle, uint32_t ip, uint16_t port, char *user) {
-  int         hash;
-  SConnHash * pNode;
-  SConnCache *pObj;
-  void *      pData = NULL;
-
-  pObj = (SConnCache *)handle;
-  if (pObj == NULL || pObj->maxSessions == 0) return NULL;
-
-  uint64_t time = taosGetTimestampMs();
-
-  hash = taosHashConn(pObj, ip, port, user);
-  pthread_mutex_lock(&pObj->mutex);
-
-  pNode = pObj->connHashList[hash];
-  while (pNode) {
-    if (time >= pObj->keepTimer + pNode->time) {
-      taosRemoveExpiredNodes(pObj, pNode, hash, time);
-      pNode = NULL;
-      break;
-    }
-
-    if (pNode->ip == ip && pNode->port == port) break;
-
-    pNode = pNode->next;
-  }
-
-  if (pNode) {
-    taosRemoveExpiredNodes(pObj, pNode->next, hash, time);
-
-    if (pNode->prev) {
-      pNode->prev->next = pNode->next;
-    } else {
-      pObj->connHashList[hash] = pNode->next;
-    }
-
-    if (pNode->next) {
-      pNode->next->prev = pNode->prev;
-    }
-
-    pData = pNode->data;
-    taosMemPoolFree(pObj->connHashMemPool, (char *)pNode);
-    pObj->total--;
-    pObj->count[hash]--;
-  }
-
-  pthread_mutex_unlock(&pObj->mutex);
-
-  if (pData) {
-    tscTrace("%p ip:0x%x:%hu:%d:%p retrieved, connections in cache:%d", pData, ip, port, hash, pNode, pObj->count[hash]);
-  }
-
-  return pData;
-}
-
-void *taosOpenConnCache(int maxSessions, void (*cleanFp)(void *), void *tmrCtrl, int64_t keepTimer) {
-  SConnHash **connHashList;
-  mpool_h     connHashMemPool;
-  SConnCache *pObj;
-
-  connHashMemPool = taosMemPoolInit(maxSessions, sizeof(SConnHash));
-  if (connHashMemPool == 0) return NULL;
-
-  connHashList = calloc(sizeof(SConnHash *), maxSessions);
-  if (connHashList == 0) {
-    taosMemPoolCleanUp(connHashMemPool);
-    return NULL;
-  }
-
-  pObj = malloc(sizeof(SConnCache));
-  if (pObj == NULL) {
-    taosMemPoolCleanUp(connHashMemPool);
-    free(connHashList);
-    return NULL;
-  }
-  memset(pObj, 0, sizeof(SConnCache));
-
-  pObj->count = calloc(sizeof(int), maxSessions);
-  pObj->total = 0;
-  pObj->keepTimer = keepTimer;
-  pObj->maxSessions = maxSessions;
-  pObj->connHashMemPool = connHashMemPool;
-  pObj->connHashList = connHashList;
-  pObj->cleanFp = cleanFp;
-  pObj->tmrCtrl = tmrCtrl;
-  taosTmrReset(taosCleanConnCache, pObj->keepTimer * 2, pObj, pObj->tmrCtrl, &pObj->pTimer);
-
-  pthread_mutex_init(&pObj->mutex, NULL);
-
-  return pObj;
-}
-
-void taosCloseConnCache(void *handle) {
-  SConnCache *pObj;
-
-  pObj = (SConnCache *)handle;
-  if (pObj == NULL || pObj->maxSessions == 0) return;
-
-  pthread_mutex_lock(&pObj->mutex);
-
-  taosTmrStopA(&(pObj->pTimer));
-
-  if (pObj->connHashMemPool) taosMemPoolCleanUp(pObj->connHashMemPool);
-
-  tfree(pObj->connHashList);
-  tfree(pObj->count)
-
-      pthread_mutex_unlock(&pObj->mutex);
-
-  pthread_mutex_destroy(&pObj->mutex);
-
-  memset(pObj, 0, sizeof(SConnCache));
-  free(pObj);
-}
diff --git a/src/client/src/tscFunctionImpl.c b/src/client/src/tscFunctionImpl.c
index 9c4f7e9c55b315263edaa4bbcadef11b6089593f..dc6f3fb5ee1e61c4b736d53cde1417cf3ffd60d2 100644
--- a/src/client/src/tscFunctionImpl.c
+++ b/src/client/src/tscFunctionImpl.c
@@ -14,20 +14,20 @@
  */
 
 #include "os.h"
+#include "qextbuffer.h"
+#include "qhistogram.h"
+#include "qinterpolation.h"
+#include "qpercentile.h"
+#include "qsyntaxtreefunction.h"
+#include "taosdef.h"
 #include "taosmsg.h"
 #include "tast.h"
-#include "textbuffer.h"
-#include "thistogram.h"
-#include "tinterpolation.h"
 #include "tlog.h"
 #include "tscJoinProcess.h"
-#include "tscSyntaxtreefunction.h"
 #include "tscompression.h"
 #include "tsqlfunction.h"
 #include "ttime.h"
-#include "taosdef.h"
 #include "tutil.h"
-#include "tpercentile.h"
 
 #define GET_INPUT_CHAR(x) (((char *)((x)->aInputElemBuf)) + ((x)->startOffset) * ((x)->inputBytes))
 #define GET_INPUT_CHAR_INDEX(x, y) (GET_INPUT_CHAR(x) + (y) * (x)->inputBytes)
diff --git a/src/client/src/tscLocal.c b/src/client/src/tscLocal.c
index 0a4d7e74d6dca4f6d2857ce6902385e92842f47b..08ef80b9ab3e07de9196adc87eb928641ca21157 100644
--- a/src/client/src/tscLocal.c
+++ b/src/client/src/tscLocal.c
@@ -21,7 +21,7 @@
 #include "tsclient.h"
 #include "taosdef.h"
 
-#include "textbuffer.h"
+#include "qextbuffer.h"
 #include "tscSecondaryMerge.h"
 #include "tschemautil.h"
 #include "tsocket.h"
diff --git a/src/client/src/tscParseInsert.c b/src/client/src/tscParseInsert.c
index 1b7ed4002be01875fa30226b3bb6e0be348c739d..db7d40f98dfd1099fd417df51a18aac445c64fae 100644
--- a/src/client/src/tscParseInsert.c
+++ b/src/client/src/tscParseInsert.c
@@ -1314,11 +1314,10 @@ int tsParseSql(SSqlObj *pSql, bool multiVnodeInsertion) {
      * the error handle callback function can rightfully restore the user defined function (fp)
      */
     if (pSql->fp != NULL && multiVnodeInsertion) {
-      assert(pSql->fetchFp == NULL);
       pSql->fetchFp = pSql->fp;
 
       // replace user defined callback function with multi-insert proxy function
-      pSql->fp = tscAsyncInsertMultiVnodesProxy;
+      pSql->fp = launchMultivnodeInsert;
     }
 
     ret = tsParseInsertSql(pSql);
diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index 419390379505a966096b733d8b75772b97c9ebed..4f4b557051c7b5a73a6bcca130c258f047ebe91f 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -28,6 +28,7 @@
 #include "tscUtil.h"
 #include "tschemautil.h"
 #include "tsclient.h"
+#include "ttokendef.h"
 
 #define DEFAULT_PRIMARY_TIMESTAMP_COL_NAME "_c0"
 
@@ -59,7 +60,7 @@ static int32_t setObjFullName(char* fullName, const char* account, SSQLToken* pD
 static void getColumnName(tSQLExprItem* pItem, char* resultFieldName, int32_t nameLength);
 static void getRevisedName(char* resultFieldName, int32_t functionId, int32_t maxLen, char* columnName);
 
-static int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIdx, tSQLExprItem* pItem, bool isResultColumn);
+static int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIdx, tSQLExprItem* pItem, bool finalResult);
 static int32_t insertResultField(SQueryInfo* pQueryInfo, int32_t outputIndex, SColumnList* pIdList, int16_t bytes,
                                  int8_t type, char* fieldName, SSqlExpr* pSqlExpr);
 static int32_t changeFunctionID(int32_t optr, int16_t* functionId);
diff --git a/src/client/src/tscServer.c b/src/client/src/tscServer.c
index a7c5b0f6b92735d44dfb62c5c6490f2e100f139f..8453fdb305b7b9ff0cb440bcf31f05a90b78a15a 100644
--- a/src/client/src/tscServer.c
+++ b/src/client/src/tscServer.c
@@ -605,7 +605,7 @@ int tscProcessSql(SSqlObj *pSql) {
       }
     }
   }
-
+  
   if (tscIsTwoStageMergeMetricQuery(pQueryInfo, 0)) {
     /*
      * (ref. line: 964)
@@ -615,24 +615,16 @@ int tscProcessSql(SSqlObj *pSql) {
      * when pSql being released, pSql->fp == NULL, it may pass the check of pSql->fp == NULL,
      * which causes deadlock. So we keep it as local variable.
      */
-    void *fp = pSql->fp;
-
     if (tscLaunchSTableSubqueries(pSql) != TSDB_CODE_SUCCESS) {
       return pRes->code;
     }
-
-    if (fp == NULL) {
-      tsem_post(&pSql->emptyRspSem);
-      tsem_wait(&pSql->rspSem);
-      tsem_post(&pSql->emptyRspSem);
-
-      // set the command flag must be after the semaphore been correctly set.
-      pSql->cmd.command = TSDB_SQL_RETRIEVE_METRIC;
-    }
-
+    
+    return pSql->res.code;
+  } else if (pSql->fp == launchMultivnodeInsert) {  // multi-vnodes insertion
+    launchMultivnodeInsert(pSql);
     return pSql->res.code;
   }
-
+  
   return doProcessSql(pSql);
 }
 
diff --git a/src/client/src/tscSql.c b/src/client/src/tscSql.c
index bbe2fa8d3a50516a884b5404affab3f53bc5d430..eb09231578b1b0770c7d8ee5386b0453f89ba509 100644
--- a/src/client/src/tscSql.c
+++ b/src/client/src/tscSql.c
@@ -13,7 +13,6 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <tast.h>
 #include "hash.h"
 #include "os.h"
 #include "tcache.h"
@@ -30,6 +29,7 @@
 #include "tsocket.h"
 #include "ttimer.h"
 #include "tutil.h"
+#include "ttokendef.h"
 
 TAOS *taos_connect_imp(const char *ip, const char *user, const char *pass, const char *db, uint16_t port,
                        void (*fp)(void *, TAOS_RES *, int), void *param, void **taos) {
diff --git a/src/client/src/tscSystem.c b/src/client/src/tscSystem.c
index 866398b7f5cfeadf1d5eda6d1354128ce8ed1c75..426570134396956d06122bfd593226cac82a224f 100644
--- a/src/client/src/tscSystem.c
+++ b/src/client/src/tscSystem.c
@@ -38,7 +38,6 @@ int     initialized = 0;
 int     slaveIndex;
 void *  tscTmr;
 void *  tscQhandle;
-void *  tscConnCache;
 void *  tscCheckDiskUsageTmr;
 int     tsInsertHeadSize;
 
@@ -188,8 +187,6 @@ void taos_init_imp() {
 
   if (tscCacheHandle == NULL) tscCacheHandle = taosCacheInit(tscTmr, refreshTime);
 
-  tscConnCache = taosOpenConnCache(tsMaxMeterConnections * 2, NULL/*taosCloseRpcConn*/, tscTmr, tsShellActivityTimer * 1000);
-
   initialized = 1;
   tscTrace("client is initialized successfully");
   tsInsertHeadSize = tsRpcHeadSize + sizeof(SShellSubmitMsg);
diff --git a/src/client/src/tscUtil.c b/src/client/src/tscUtil.c
index b655832f1159efe399cfeec94f8cc00cbb671f38..5314f35757d612dfe07ea50af6f656baf9f62738 100644
--- a/src/client/src/tscUtil.c
+++ b/src/client/src/tscUtil.c
@@ -2105,7 +2105,6 @@ SSqlObj* createSubqueryObj(SSqlObj* pSql, int16_t tableIndex, void (*fp)(), void
 
 void tscDoQuery(SSqlObj* pSql) {
   SSqlCmd* pCmd = &pSql->cmd;
-  void*    fp = pSql->fp;
   
   pSql->res.code = TSDB_CODE_SUCCESS;
   
@@ -2121,7 +2120,6 @@ void tscDoQuery(SSqlObj* pSql) {
     } else {
       // pSql may be released in this function if it is a async insertion.
       tscProcessSql(pSql);
-      if (NULL == fp) tscProcessMultiVnodesInsert(pSql);
     }
   }
 }
@@ -2321,3 +2319,94 @@ void tscTryQueryNextClause(SSqlObj* pSql, void (*queryFp)()) {
     tscProcessSql(pSql);
   }
 }
+
+typedef struct SinsertSupporter {
+  SSubqueryState* pState;
+  SSqlObj*  pSql;
+} SinsertSupporter;
+
+void multiVnodeInsertMerge(void* param, TAOS_RES* tres, int numOfRows) {
+  SinsertSupporter *pSupporter = (SinsertSupporter *)param;
+  SSqlObj* pParentObj = pSupporter->pSql;
+  SSqlCmd* pParentCmd = &pParentObj->cmd;
+  
+  SSubqueryState* pState = pSupporter->pState;
+  int32_t total = pState->numOfTotal;
+  
+  // increase the total inserted rows
+  if (numOfRows > 0) {
+    pParentObj->res.numOfRows += numOfRows;
+  }
+  
+  int32_t completed = atomic_add_fetch_32(&pState->numOfCompleted, 1);
+  if (completed < total) {
+    return;
+  }
+  
+  tscTrace("%p Async insertion completed, total inserted:%d", pParentObj, pParentObj->res.numOfRows);
+  
+  // release data block data
+  pParentCmd->pDataBlocks = tscDestroyBlockArrayList(pParentCmd->pDataBlocks);
+  
+  // restore user defined fp
+  pParentObj->fp = pParentObj->fetchFp;
+  
+  // all data has been sent to vnode, call user function
+  (*pParentObj->fp)(pParentObj->param, tres, numOfRows);
+}
+
+int32_t launchMultivnodeInsert(SSqlObj *pSql) {
+  SSqlRes *pRes = &pSql->res;
+  SSqlCmd *pCmd = &pSql->cmd;
+  
+  pRes->qhandle = 1;  // hack the qhandle check
+  SDataBlockList *pDataBlocks = pCmd->pDataBlocks;
+  
+  pSql->pSubs = calloc(pDataBlocks->nSize, POINTER_BYTES);
+  pSql->numOfSubs = pDataBlocks->nSize;
+  assert(pDataBlocks->nSize > 0);
+  
+  tscTrace("%p submit data to %d vnode(s)", pSql, pDataBlocks->nSize);
+  SSubqueryState *pState = calloc(1, sizeof(SSubqueryState));
+  pState->numOfTotal = pSql->numOfSubs;
+  
+  pRes->code = TSDB_CODE_SUCCESS;
+  
+  int32_t i = 0;
+  for (; i < pSql->numOfSubs; ++i) {
+    SinsertSupporter* pSupporter = calloc(1, sizeof(SinsertSupporter));
+    pSupporter->pSql = pSql;
+    pSupporter->pState = pState;
+    
+    SSqlObj *pNew = createSubqueryObj(pSql, 0, multiVnodeInsertMerge, pSupporter, NULL);
+    if (pNew == NULL) {
+      tscError("%p failed to malloc buffer for subObj, orderOfSub:%d, reason:%s", pSql, i, strerror(errno));
+      break;
+    }
+    
+    pSql->pSubs[i] = pNew;
+    tscTrace("%p sub:%p create subObj success. orderOfSub:%d", pSql, pNew, i);
+  }
+  
+  if (i < pSql->numOfSubs) {
+    tscError("%p failed to prepare subObj structure and launch sub-insertion", pSql);
+    pRes->code = TSDB_CODE_CLI_OUT_OF_MEMORY;
+    return pRes->code;  // free all allocated resource
+  }
+  
+  for (int32_t j = 0; j < pSql->numOfSubs; ++j) {
+    SSqlObj *pSub = pSql->pSubs[j];
+    pSub->cmd.command = TSDB_SQL_INSERT;
+    int32_t code = tscCopyDataBlockToPayload(pSub, pDataBlocks->pData[j]);
+    
+    if (code != TSDB_CODE_SUCCESS) {
+      tscTrace("%p prepare submit data block failed in async insertion, vnodeIdx:%d, total:%d, code:%d", pSql, j,
+               pDataBlocks->nSize, code);
+    }
+    
+    tscTrace("%p sub:%p launch sub insert, orderOfSub:%d", pSql, pSub, j);
+    tscProcessSql(pSub);
+  }
+  
+  return TSDB_CODE_SUCCESS;
+}
diff --git a/src/inc/tpercentile.h b/src/inc/qpercentile.h
similarity index 98%
rename from src/inc/tpercentile.h
rename to src/inc/qpercentile.h
index b9cf50e0bbf24357b729f8bc39996f589d6c18fc..73430bd05ccb07df93c1fc9869539b504c6e618e 100644
--- a/src/inc/tpercentile.h
+++ b/src/inc/qpercentile.h
@@ -16,7 +16,7 @@
 #ifndef TDENGINE_TPERCENTILE_H
 #define TDENGINE_TPERCENTILE_H
 
-#include "textbuffer.h"
+#include "qextbuffer.h"
 
 typedef struct MinMaxEntry {
   union {
diff --git a/src/mnode/src/mgmtTable.c b/src/mnode/src/mgmtTable.c
index ee0f19b89bc3e1474acc3d76d2018f65f77ca8b5..9c4e0b57a10baec1c3c4883aebf33ee3825694aa 100644
--- a/src/mnode/src/mgmtTable.c
+++ b/src/mnode/src/mgmtTable.c
@@ -14,22 +14,11 @@
  */
 
 #define _DEFAULT_SOURCE
-#include "os.h"
-#include "taoserror.h"
-#include "taosmsg.h"
-#include "tast.h"
-#include "textbuffer.h"
-#include "tschemautil.h"
-#include "tscompression.h"
-#include "tskiplist.h"
-#include "tsqlfunction.h"
-#include "tstatus.h"
-#include "ttime.h"
-#include "mnode.h"
+#include "mgmtTable.h"
 #include "mgmtAcct.h"
 #include "mgmtChildTable.h"
-#include "mgmtDb.h"
 #include "mgmtDClient.h"
+#include "mgmtDb.h"
 #include "mgmtDnode.h"
 #include "mgmtGrant.h"
 #include "mgmtMnode.h"
@@ -37,9 +26,20 @@
 #include "mgmtProfile.h"
 #include "mgmtShell.h"
 #include "mgmtSuperTable.h"
-#include "mgmtTable.h"
 #include "mgmtUser.h"
 #include "mgmtVgroup.h"
+#include "mnode.h"
+#include "os.h"
+#include "qextbuffer.h"
+#include "taoserror.h"
+#include "taosmsg.h"
+#include "tast.h"
+#include "tschemautil.h"
+#include "tscompression.h"
+#include "tskiplist.h"
+#include "tsqlfunction.h"
+#include "tstatus.h"
+#include "ttime.h"
 
 extern void *tsNormalTableSdb;
 extern void *tsChildTableSdb;
diff --git a/src/query/inc/textbuffer.h b/src/query/inc/qextbuffer.h
similarity index 100%
rename from src/query/inc/textbuffer.h
rename to src/query/inc/qextbuffer.h
diff --git a/src/query/inc/thistogram.h b/src/query/inc/qhistogram.h
similarity index 100%
rename from src/query/inc/thistogram.h
rename to src/query/inc/qhistogram.h
diff --git a/src/query/inc/tinterpolation.h b/src/query/inc/qinterpolation.h
similarity index 98%
rename from src/query/inc/tinterpolation.h
rename to src/query/inc/qinterpolation.h
index f4b327bcbec82b2b9ca8e2f5c92b044700240dbc..c8ebd850b61cdc69e5816837d5a439a10ba99e43 100644
--- a/src/query/inc/tinterpolation.h
+++ b/src/query/inc/qinterpolation.h
@@ -20,6 +20,10 @@
 extern "C" {
 #endif
 
+#include "os.h"
+#include "taosdef.h"
+#include "qextbuffer.h"
+
 typedef struct SInterpolationInfo {
   int64_t startTimestamp;
   int32_t order;                // order [asc/desc]
diff --git a/src/query/inc/tresultBuf.h b/src/query/inc/qresultBuf.h
similarity index 99%
rename from src/query/inc/tresultBuf.h
rename to src/query/inc/qresultBuf.h
index 8f30ff7c61555e993838989aecb32a81d1c414bf..346dc2d00c66e33cf63cffdb3c748cfecad02832 100644
--- a/src/query/inc/tresultBuf.h
+++ b/src/query/inc/qresultBuf.h
@@ -21,7 +21,7 @@ extern "C" {
 #endif
 
 #include "os.h"
-#include "textbuffer.h"
+#include "qextbuffer.h"
 
 typedef struct SIDList {
   uint32_t alloc;
diff --git a/src/query/inc/qsqlparser.h b/src/query/inc/qsqlparser.h
index 7a1322be10fb24581b9f0d38db173a7d7f86612e..064ded2fad49d3001596d6e2e7ac762ce59829b9 100644
--- a/src/query/inc/qsqlparser.h
+++ b/src/query/inc/qsqlparser.h
@@ -329,6 +329,18 @@ void tSQLSetColumnType(TAOS_FIELD *pField, SSQLToken *pToken);
 
 void *ParseAlloc(void *(*mallocProc)(size_t));
 
+enum {
+  TSQL_NODE_TYPE_EXPR = 0x1,
+  TSQL_NODE_TYPE_ID = 0x2,
+  TSQL_NODE_TYPE_VALUE = 0x4,
+};
+
+#define NON_ARITHMEIC_EXPR 0
+#define NORMAL_ARITHMETIC 1
+#define AGG_ARIGHTMEIC    2
+
+int32_t tSQLParse(SSqlInfo *pSQLInfo, const char *pSql);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/query/inc/tscSyntaxtreefunction.h b/src/query/inc/qsyntaxtreefunction.h
similarity index 100%
rename from src/query/inc/tscSyntaxtreefunction.h
rename to src/query/inc/qsyntaxtreefunction.h
diff --git a/src/query/src/tscAst.c b/src/query/src/qast.c
similarity index 99%
rename from src/query/src/tscAst.c
rename to src/query/src/qast.c
index ef83083a2c5aa91fdbbb4db5bbe8330ae188d594..807fd5e5aaf409e6797f20070180c2d19e387437 100644
--- a/src/query/src/tscAst.c
+++ b/src/query/src/qast.c
@@ -14,18 +14,17 @@
  */
 
 #include "os.h"
+#include "qsqlparser.h"
+#include "qsyntaxtreefunction.h"
 #include "taosdef.h"
 #include "taosmsg.h"
 #include "tast.h"
 #include "tlog.h"
-#include "tscSyntaxtreefunction.h"
 #include "tschemautil.h"
 #include "tsqlfunction.h"
 #include "tstoken.h"
 #include "ttokendef.h"
-#include "taosdef.h"
 #include "tutil.h"
-#include "qsqlparser.h"
 
 /*
  *
@@ -648,7 +647,7 @@ int32_t intersect(tQueryResultset *pLeft, tQueryResultset *pRight, tQueryResults
 /*
  * traverse the result and apply the function to each item to check if the item is qualified or not
  */
-static void tSQLListTraverseOnResult(struct tSQLBinaryExpr *pExpr, __result_filter_fn_t fp, tQueryResultset *pResult) {
+static UNUSED_FUNC void tSQLListTraverseOnResult(struct tSQLBinaryExpr *pExpr, __result_filter_fn_t fp, tQueryResultset *pResult) {
   assert(pExpr->pLeft->nodeType == TSQL_NODE_COL && pExpr->pRight->nodeType == TSQL_NODE_VALUE);
 
   // brutal force scan the result list and check for each item in the list
@@ -705,7 +704,7 @@ static bool filterItem(tSQLBinaryExpr *pExpr, const void *pItem, SBinaryFilterSu
  * @param pSchema   tag schemas
  * @param fp        filter callback function
  */
-static void tSQLBinaryTraverseOnResult(tSQLBinaryExpr *pExpr, tQueryResultset *pResult, SBinaryFilterSupp *param) {
+static UNUSED_FUNC void tSQLBinaryTraverseOnResult(tSQLBinaryExpr *pExpr, tQueryResultset *pResult, SBinaryFilterSupp *param) {
   int32_t n = 0;
   for (int32_t i = 0; i < pResult->num; ++i) {
     void *pItem = pResult->pRes[i];
diff --git a/src/query/src/textbuffer.c b/src/query/src/qextbuffer.c
similarity index 99%
rename from src/query/src/textbuffer.c
rename to src/query/src/qextbuffer.c
index 056fe808588e673126081355ca31020f672ab368..92f5175b9899f0ab1fc942d9b132c0f4a4fc818f 100644
--- a/src/query/src/textbuffer.c
+++ b/src/query/src/qextbuffer.c
@@ -12,14 +12,14 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
+#include "qextbuffer.h"
 #include "os.h"
 #include "taos.h"
+#include "taosdef.h"
 #include "taosmsg.h"
-#include "textbuffer.h"
 #include "tlog.h"
 #include "tsqlfunction.h"
 #include "ttime.h"
-#include "taosdef.h"
 #include "tutil.h"
 
 #define COLMODEL_GET_VAL(data, schema, allrow, rowId, colId) \
diff --git a/src/query/src/thistogram.c b/src/query/src/qhistogram.c
similarity index 99%
rename from src/query/src/thistogram.c
rename to src/query/src/qhistogram.c
index 31045a4957be59d924eb70fb0876eefb6715aaa2..26482e9f142728f0b097511f98ca2e297e34ef7b 100644
--- a/src/query/src/thistogram.c
+++ b/src/query/src/qhistogram.c
@@ -14,10 +14,10 @@
  */
 #include "os.h"
 
+#include "qhistogram.h"
+#include "taosdef.h"
 #include "taosmsg.h"
-#include "thistogram.h"
 #include "tlosertree.h"
-#include "taosdef.h"
 
 /**
  *
diff --git a/src/query/src/tinterpolation.c b/src/query/src/qinterpolation.c
similarity index 99%
rename from src/query/src/tinterpolation.c
rename to src/query/src/qinterpolation.c
index 1a9da44788f5c9bc5a066bd927beaefd0f58ea34..1731e16ed82703753c59d2a8f34411b39eba8c3b 100644
--- a/src/query/src/tinterpolation.c
+++ b/src/query/src/qinterpolation.c
@@ -13,12 +13,12 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include "qinterpolation.h"
 #include "os.h"
+#include "qextbuffer.h"
+#include "taosdef.h"
 #include "taosmsg.h"
-#include "textbuffer.h"
-#include "tinterpolation.h"
 #include "tsqlfunction.h"
-#include "taosdef.h"
 
 #define INTERPOL_IS_ASC_INTERPOL(interp) ((interp)->order == TSQL_SO_ASC)
 
diff --git a/src/query/src/tscSQLParserImpl.c b/src/query/src/qparserImpl.c
similarity index 100%
rename from src/query/src/tscSQLParserImpl.c
rename to src/query/src/qparserImpl.c
diff --git a/src/query/src/tpercentile.c b/src/query/src/qpercentile.c
similarity index 99%
rename from src/query/src/tpercentile.c
rename to src/query/src/qpercentile.c
index 6e1c28c516ce08e233b7c9afa418e571bd94e051..3b12dee0538200903ae19f2a364ea2b75543a1ae 100644
--- a/src/query/src/tpercentile.c
+++ b/src/query/src/qpercentile.c
@@ -15,11 +15,10 @@
 
 #include "os.h"
 
-#include "taosmsg.h"
+#include "qpercentile.h"
 #include "taosdef.h"
+#include "taosmsg.h"
 #include "tlog.h"
-#include "taosdef.h"
-#include "tpercentile.h"
 
 tExtMemBuffer *releaseBucketsExceptFor(tMemBucket *pMemBucket, int16_t segIdx, int16_t slotIdx) {
   tExtMemBuffer *pBuffer = NULL;
diff --git a/src/query/src/tresultBuf.c b/src/query/src/qresultBuf.c
similarity index 99%
rename from src/query/src/tresultBuf.c
rename to src/query/src/qresultBuf.c
index 11e17cc5a3437c8c03176cb2ead3318bb9a42d88..fa7c59be4e692885f812075f034936cb37e5d3ce 100644
--- a/src/query/src/tresultBuf.c
+++ b/src/query/src/qresultBuf.c
@@ -1,9 +1,9 @@
+#include "qresultBuf.h"
 #include "hash.h"
+#include "qextbuffer.h"
 #include "taoserror.h"
-#include "textbuffer.h"
 #include "tlog.h"
 #include "tsqlfunction.h"
-#include "tresultBuf.h"
 
 #define DEFAULT_INTERN_BUF_SIZE 16384L
 
diff --git a/src/query/src/tscSyntaxtreefunction.c b/src/query/src/qsyntaxtreefunction.c
similarity index 99%
rename from src/query/src/tscSyntaxtreefunction.c
rename to src/query/src/qsyntaxtreefunction.c
index e3c00ed59d1da9ee6e042f748a6bf6f586f8bd2f..d21f7dab736b1b14579f3b207da89695e93a1077 100644
--- a/src/query/src/tscSyntaxtreefunction.c
+++ b/src/query/src/qsyntaxtreefunction.c
@@ -15,7 +15,7 @@
 
 #include "os.h"
 
-#include "tscSyntaxtreefunction.h"
+#include "qsyntaxtreefunction.h"
 #include "taosdef.h"
 #include "tutil.h"
 
diff --git a/src/query/src/ttokenizer.c b/src/query/src/qtokenizer.c
similarity index 100%
rename from src/query/src/ttokenizer.c
rename to src/query/src/qtokenizer.c
diff --git a/src/query/inc/tcache.h b/src/util/inc/tcache.h
similarity index 100%
rename from src/query/inc/tcache.h
rename to src/util/inc/tcache.h
diff --git a/src/client/src/tcache.c b/src/util/src/tcache.c
similarity index 100%
rename from src/client/src/tcache.c
rename to src/util/src/tcache.c
diff --git a/src/vnode/detail/inc/vnodeRead.h b/src/vnode/detail/inc/vnodeRead.h
index 2758cfe1d9610257c7ddf0658874a7ee57511fc0..232a92608c37b54fdbfe0291facca818afcbbda8 100644
--- a/src/vnode/detail/inc/vnodeRead.h
+++ b/src/vnode/detail/inc/vnodeRead.h
@@ -21,9 +21,9 @@ extern "C" {
 #endif
 
 #include "os.h"
-#include "tresultBuf.h"
+#include "qresultBuf.h"
 
-#include "tinterpolation.h"
+#include "qinterpolation.h"
 #include "vnodeTagMgmt.h"
 
 /*
diff --git a/src/vnode/detail/src/vnodeQueryImpl.c b/src/vnode/detail/src/vnodeQueryImpl.c
index 2cdcc9130010c12d10553a6089f7ae441d7e94e1..80e073567261e6572bf786646510effac54099d2 100644
--- a/src/vnode/detail/src/vnodeQueryImpl.c
+++ b/src/vnode/detail/src/vnodeQueryImpl.c
@@ -16,11 +16,11 @@
 #include "hash.h"
 #include "hashfunc.h"
 #include "os.h"
+#include "qextbuffer.h"
 #include "taosmsg.h"
-#include "textbuffer.h"
 #include "ttime.h"
 
-#include "tinterpolation.h"
+#include "qinterpolation.h"
 #include "tscJoinProcess.h"
 #include "tscSecondaryMerge.h"
 #include "tscompression.h"
diff --git a/src/vnode/detail/src/vnodeQueryProcess.c b/src/vnode/detail/src/vnodeQueryProcess.c
index ae51365918b142e392dcffa27a6b071543f3d02e..cedb76b4accda46e934694cdbb6de416dcc8f75b 100644
--- a/src/vnode/detail/src/vnodeQueryProcess.c
+++ b/src/vnode/detail/src/vnodeQueryProcess.c
@@ -16,8 +16,8 @@
 #define _DEFAULT_SOURCE
 #include "os.h"
 
+#include "qextbuffer.h"
 #include "taosmsg.h"
-#include "textbuffer.h"
 #include "tscJoinProcess.h"
 #include "ttime.h"
 #include "vnode.h"
diff --git a/src/vnode/detail/src/vnodeRead.c b/src/vnode/detail/src/vnodeRead.c
index f21294a68e0928b55ebd7fcff28f1eb818af171e..87047f803989131c435ffe1af0b012e63ee9d53d 100644
--- a/src/vnode/detail/src/vnodeRead.c
+++ b/src/vnode/detail/src/vnodeRead.c
@@ -19,9 +19,9 @@
 #include "hash.h"
 #include "hashfunc.h"
 #include "ihash.h"
+#include "qextbuffer.h"
 #include "taosmsg.h"
 #include "tast.h"
-#include "textbuffer.h"
 #include "tscJoinProcess.h"
 #include "tscompression.h"
 #include "vnode.h"
diff --git a/src/vnode/detail/src/vnodeSupertableQuery.c b/src/vnode/detail/src/vnodeSupertableQuery.c
index 038577bd8d02bc490d283b286b1f4f3d6fb2749b..349e67e3a239d31cbb05a58482fa592d15570e30 100644
--- a/src/vnode/detail/src/vnodeSupertableQuery.c
+++ b/src/vnode/detail/src/vnodeSupertableQuery.c
@@ -14,12 +14,12 @@
  */
 
 #define _DEFAULT_SOURCE
-#include "os.h"
 #include "mnode.h"
-#include "textbuffer.h"
+#include "os.h"
+#include "qextbuffer.h"
+#include "tast.h"
 #include "tschemautil.h"
 #include "tsqlfunction.h"
-#include "tast.h"
 //#include "vnodeTagMgmt.h"
 
 typedef struct SSyntaxTreeFilterSupporter {
diff --git a/src/vnode/detail/src/vnodeTagMgmt.c b/src/vnode/detail/src/vnodeTagMgmt.c
index d3e22ec00adfbf418264888ea01a4940723df2a6..9bb0191afe07ab7022890f339805a7c83f0d01fb 100644
--- a/src/vnode/detail/src/vnodeTagMgmt.c
+++ b/src/vnode/detail/src/vnodeTagMgmt.c
@@ -16,12 +16,12 @@
 #define _DEFAULT_SOURCE
 #include "os.h"
 
+#include "qextbuffer.h"
 #include "taosdef.h"
-#include "tlog.h"
-#include "tutil.h"
 #include "taosmsg.h"
-#include "textbuffer.h"
 #include "tast.h"
+#include "tlog.h"
+#include "tutil.h"
 #include "vnodeTagMgmt.h"
 
 #define GET_TAG_VAL_POINTER(s, col, sc, t) ((t *)(&((s)->tags[getColumnModelOffset(sc, col)])))