diff --git a/src/inc/query.h b/src/inc/query.h
index cdadd4759fcfd2b8ae5b1ba8a431dbb56bfac08c..10ee0249b6730fc58881f2e47ef3425c74cfe36d 100644
--- a/src/inc/query.h
+++ b/src/inc/query.h
@@ -77,6 +77,12 @@ int32_t qDumpRetrieveResult(qinfo_t qinfo, SRetrieveTableRsp** pRsp, int32_t* co
  */
 bool qHasMoreResultsToRetrieve(qinfo_t qinfo);
 
+/**
+ * kill current ongoing query and free query handle automatically
+ * @param qinfo
+ */
+int32_t qKillQuery(qinfo_t qinfo);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 97d9efa6188cd6da634adeeb3bf87ff7f0746938..85d4acdfed399839b0a2efcb915e67a5ad19746d 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -5846,9 +5846,6 @@ void qDestroyQueryInfo(qinfo_t qHandle) {
     return;
   }
 
-  // set the query is cancelled
-  setQueryKilled(pQInfo);
-
   int16_t ref = T_REF_DEC(pQInfo);
   if (ref == 0) {
     doDestoryQueryInfo(pQInfo);
@@ -5865,11 +5862,7 @@ void qTableQuery(qinfo_t qinfo) {
 
   if (isQueryKilled(pQInfo)) {
     qTrace("QInfo:%p it is already killed, abort", pQInfo);
-
-    int16_t ref = T_REF_DEC(pQInfo);
-    if (ref == 0) {
-      doDestoryQueryInfo(pQInfo);
-    }
+    qDestroyQueryInfo(pQInfo);
     return;
   }
 
@@ -5885,10 +5878,7 @@ void qTableQuery(qinfo_t qinfo) {
   }
 
   sem_post(&pQInfo->dataReady);
-  int16_t ref = T_REF_DEC(pQInfo);
-  if (ref == 0) {
-    doDestoryQueryInfo(pQInfo);
-  }
+  qDestroyQueryInfo(pQInfo);
 }
 
 int32_t qRetrieveQueryResultInfo(qinfo_t qinfo) {
@@ -5914,7 +5904,8 @@ int32_t qRetrieveQueryResultInfo(qinfo_t qinfo) {
 bool qHasMoreResultsToRetrieve(qinfo_t qinfo) {
   SQInfo *pQInfo = (SQInfo *)qinfo;
 
-  if (isValidQInfo(pQInfo) || pQInfo->code != TSDB_CODE_SUCCESS) {
+  if (!isValidQInfo(pQInfo) || pQInfo->code != TSDB_CODE_SUCCESS) {
+    qTrace("QInfo:%p invalid qhandle or error occurs, abort query, code:%x", pQInfo, pQInfo->code);
     return false;
   }
 
@@ -5932,6 +5923,7 @@ bool qHasMoreResultsToRetrieve(qinfo_t qinfo) {
 
   if (ret) {
     T_REF_INC(pQInfo);
+    qTrace("QInfo:%p has more results waits for client retrieve", pQInfo);
   }
 
   return ret;
@@ -5979,6 +5971,19 @@ int32_t qDumpRetrieveResult(qinfo_t qinfo, SRetrieveTableRsp **pRsp, int32_t *co
   return code;
 }
 
+int32_t qKillQuery(qinfo_t qinfo) {
+  SQInfo *pQInfo = (SQInfo *)qinfo;
+
+  if (pQInfo == NULL || !isValidQInfo(pQInfo)) {
+    return TSDB_CODE_QRY_INVALID_QHANDLE;
+  }
+
+  setQueryKilled(pQInfo);
+  qDestroyQueryInfo(pQInfo);
+
+  return TSDB_CODE_SUCCESS;
+}
+
 static void buildTagQueryResult(SQInfo* pQInfo) {
   SQueryRuntimeEnv *pRuntimeEnv = &pQInfo->runtimeEnv;
   SQuery *          pQuery = pRuntimeEnv->pQuery;
diff --git a/src/vnode/src/vnodeRead.c b/src/vnode/src/vnodeRead.c
index 4c36703e6b7f2dec5dc6866bdd1a5cb8a4f95bf0..9dce61704f9c6dcefa17cc5fb4fa7091418aa21e 100644
--- a/src/vnode/src/vnodeRead.c
+++ b/src/vnode/src/vnodeRead.c
@@ -80,14 +80,12 @@ static int32_t vnodeProcessQueryMsg(SVnodeObj *pVnode, SReadMsg *pReadMsg) {
   memset(pRet, 0, sizeof(SRspRet));
 
   // qHandle needs to be freed correctly
-  if (pReadMsg->rpcMsg.code != TSDB_CODE_SUCCESS) {
-    assert(pReadMsg->rpcMsg.contLen > 0);
-
+  if (pReadMsg->rpcMsg.code != TSDB_CODE_RPC_NETWORK_UNAVAIL) {
     SRetrieveTableMsg* killQueryMsg = (SRetrieveTableMsg*) pReadMsg->pCont;
     killQueryMsg->free = htons(killQueryMsg->free);
     killQueryMsg->qhandle = htobe64(killQueryMsg->qhandle);
 
-    assert(killQueryMsg->free == 1);
+    assert(pReadMsg->rpcMsg.contLen > 0 && killQueryMsg->free == 1);
     qDestroyQueryInfo((qinfo_t) killQueryMsg->qhandle);
 
     return TSDB_CODE_SUCCESS;
@@ -130,10 +128,28 @@ static int32_t vnodeProcessFetchMsg(SVnodeObj *pVnode, SReadMsg *pReadMsg) {
 
   SRetrieveTableMsg *pRetrieve = pCont;
   void *pQInfo = (void*) htobe64(pRetrieve->qhandle);
+  pRetrieve->free = htons(pRetrieve->free);
+
   memset(pRet, 0, sizeof(SRspRet));
 
+  if (pRetrieve->free == 1) {
+    vTrace("vgId:%d, QInfo:%p, retrieve msg received to kill query and free qhandle", pVnode->vgId, pQInfo);
+    int32_t ret = qKillQuery(pQInfo);
+
+    pRet->rsp = (SRetrieveTableRsp *)rpcMallocCont(sizeof(SRetrieveTableRsp));
+    pRet->len = sizeof(SRetrieveTableRsp);
+
+    memset(pRet->rsp, 0, sizeof(SRetrieveTableRsp));
+    SRetrieveTableRsp* pRsp = pRet->rsp;
+    pRsp->numOfRows = 0;
+    pRsp->completed = true;
+    pRsp->useconds  = 0;
+
+    return ret;
+  }
+
   vTrace("vgId:%d, QInfo:%p, retrieve msg is received", pVnode->vgId, pQInfo);
-  
+
   int32_t code = qRetrieveQueryResultInfo(pQInfo);
   if (code != TSDB_CODE_SUCCESS) {
     //TODO
@@ -146,8 +162,7 @@ static int32_t vnodeProcessFetchMsg(SVnodeObj *pVnode, SReadMsg *pReadMsg) {
     if (qHasMoreResultsToRetrieve(pQInfo)) {
       pRet->qhandle = pQInfo;
       code = TSDB_CODE_VND_ACTION_NEED_REPROCESSED;
-    } else {
-      // no further execution invoked, release the ref to vnode
+    } else { // no further execution invoked, release the ref to vnode
       qDestroyQueryInfo(pQInfo);
       vnodeRelease(pVnode);
     }
diff --git a/tests/examples/c/demo.c b/tests/examples/c/demo.c
index 55a19eb5f90e27d9040e1d15c81909562b6c608b..5b54efe22d5560984febe981126963ac8b3c205f 100644
--- a/tests/examples/c/demo.c
+++ b/tests/examples/c/demo.c
@@ -115,15 +115,15 @@ int main(int argc, char *argv[]) {
   
   printf("success to connect to server\n");
 //  doQuery(taos, "select c1,count(*) from group_db0.group_mt0 where c1<8 group by c1");
-  doQuery(taos, "select * from test.m1");
+//  doQuery(taos, "select * from test.m1");
 
 //  multiThreadTest(1, taos);
 //  doQuery(taos, "select tbname from test.m1");
 //   doQuery(taos, "select max(c1), min(c2), sum(c3), avg(c4), first(c7), last(c8), first(c9) from lm2_db0.lm2_stb0 where ts >= 1537146000000 and ts <= 1543145400000 and tbname in ('lm2_tb0') interval(1s) group by t1");
 //   doQuery(taos, "select max(c1), min(c2), sum(c3), avg(c4), first(c7), last(c8), first(c9) from lm2_db0.lm2_stb0 where ts >= 1537146000000 and ts <= 1543145400000 and tbname in ('lm2_tb0', 'lm2_tb1', 'lm2_tb2') interval(1s)");
-//  for(int32_t i = 0; i < 100000; ++i) {
-//    doQuery(taos, "insert into t1 values(now, 2)");
-//  }
+  for(int32_t i = 0; i < 200; ++i) {
+    doQuery(taos, "select * from lm2_db0.lm2_stb0");
+  }
 //  doQuery(taos, "create table t1(ts timestamp, k binary(12), f nchar(2))");
   
   taos_close(taos);