diff --git a/include/common/systable.h b/include/common/systable.h
index 8b0bb4a3fba107e1d74bee6885c39ae06d425a19..d2c28941c77ae92c7a52c6e9df89de1650ad4360 100644
--- a/include/common/systable.h
+++ b/include/common/systable.h
@@ -52,6 +52,7 @@ extern "C" {
 #define TSDB_PERFS_TABLE_OFFSETS       "offsets"
 #define TSDB_PERFS_TABLE_TRANS         "trans"
 #define TSDB_PERFS_TABLE_STREAMS       "streams"
+#define TSDB_PERFS_TABLE_APPS          "apps"
 
 typedef struct SSysDbTableSchema {
   const char*   name;
diff --git a/include/common/tmsg.h b/include/common/tmsg.h
index 80e8d291970cac19eb74b51a507d937848305d61..81123ea3d977112cd1fb7c12bda77e8dbd2ddd2f 100644
--- a/include/common/tmsg.h
+++ b/include/common/tmsg.h
@@ -1982,16 +1982,17 @@ typedef struct {
 
 typedef struct {
   int64_t tid;
-  int32_t status;
+  char    status[TSDB_JOB_STATUS_LEN];
 } SQuerySubDesc;
 
 typedef struct {
   char     sql[TSDB_SHOW_SQL_LEN];
   uint64_t queryId;
   int64_t  useconds;
-  int64_t  stime;
+  int64_t  stime;            // timestamp precision ms
   int64_t  reqRid;
   int32_t  pid;
+  bool     stableQuery;
   char     fqdn[TSDB_FQDN_LEN];
   int32_t  subPlanNum;
   SArray*  subDesc;  // SArray<SQuerySubDesc>
diff --git a/include/libs/nodes/querynodes.h b/include/libs/nodes/querynodes.h
index 33cc4a9c865241d39ca2b94317f93ffff4694581..42c7c2795131eff4c5df174ee8f88676bd6c0d52 100644
--- a/include/libs/nodes/querynodes.h
+++ b/include/libs/nodes/querynodes.h
@@ -352,6 +352,7 @@ typedef struct SQuery {
   SArray*                 pPlaceholderValues;
   SNode*                  pPrepareRoot;
   struct SParseMetaCache* pMetaCache;
+  bool                    stableQuery;
 } SQuery;
 
 void nodesWalkSelectStmt(SSelectStmt* pSelect, ESqlClause clause, FNodeWalker walker, void* pContext);
diff --git a/include/util/tdef.h b/include/util/tdef.h
index 1fa8ad19126f2fe69b4500eac2d9dfdd2665ba17..73b40c71d85827f6634943b2d8d397c066a6961f 100644
--- a/include/util/tdef.h
+++ b/include/util/tdef.h
@@ -241,6 +241,7 @@ typedef enum ELogicConditionType {
 #define TSDB_USET_PASSWORD_LEN 129
 #define TSDB_VERSION_LEN       12
 #define TSDB_LABEL_LEN         8
+#define TSDB_JOB_STATUS_LEN    32
 
 #define TSDB_CLUSTER_ID_LEN     40
 #define TSDB_FQDN_LEN           128
diff --git a/source/client/inc/clientInt.h b/source/client/inc/clientInt.h
index d72aa39e4c76d1f6397df2d98f2a02bb8938456b..69a24e20cd7e4a6d20efc9c12f1766f06af050ae 100644
--- a/source/client/inc/clientInt.h
+++ b/source/client/inc/clientInt.h
@@ -45,7 +45,7 @@ extern "C" {
 
 #define ERROR_MSG_BUF_DEFAULT_SIZE 512
 #define HEARTBEAT_INTERVAL         1500  // ms
-#define SYNC_ON_TOP_OF_ASYNC       0
+#define SYNC_ON_TOP_OF_ASYNC       1
 
 enum {
   RES_TYPE__QUERY = 1,
@@ -213,6 +213,7 @@ typedef struct SRequestObj {
   SArray*              tableList;
   SQueryExecMetric     metric;
   SRequestSendRecvBody body;
+  bool                 stableQuery;
 
   uint32_t             prevCode; //previous error code: todo refactor, add update flag for catalog
   uint32_t             retry;
@@ -294,7 +295,7 @@ void* openTransporter(const char* user, const char* auth, int32_t numOfThreads);
 bool persistConnForSpecificMsg(void* parenct, tmsg_t msgType);
 void processMsgFromServer(void* parent, SRpcMsg* pMsg, SEpSet* pEpSet);
 
-TAOS* taos_connect_internal(const char* ip, const char* user, const char* pass, const char* auth, const char* db,
+STscObj* taos_connect_internal(const char* ip, const char* user, const char* pass, const char* auth, const char* db,
                             uint16_t port, int connType);
 
 SRequestObj* launchQuery(STscObj* pTscObj, const char* sql, int sqlLen);
@@ -305,6 +306,8 @@ int32_t getPlan(SRequestObj* pRequest, SQuery* pQuery, SQueryPlan** pPlan, SArra
 
 int32_t buildRequest(STscObj* pTscObj, const char* sql, int sqlLen, SRequestObj** pRequest);
 
+void taos_close_internal(void *taos);
+
 // --- heartbeat
 // global, called by mgmt
 int  hbMgrInit();
diff --git a/source/client/inc/clientStmt.h b/source/client/inc/clientStmt.h
index 936fb92fc4019842485e7051abf161aee8a7d858..c2b5d1de6f9427c1c1aba506ceb9d446a883ce81 100644
--- a/source/client/inc/clientStmt.h
+++ b/source/client/inc/clientStmt.h
@@ -107,7 +107,7 @@ typedef struct STscStmt {
 #define STMT_RET(c) do { int32_t _code = c; if (_code != TSDB_CODE_SUCCESS) { terrno = _code; } return _code; } while (0)
 #define STMT_ERR_JRET(c) do { code = c; if (code != TSDB_CODE_SUCCESS) { terrno = code; goto _return; } } while (0)
 
-TAOS_STMT *stmtInit(TAOS *taos);
+TAOS_STMT *stmtInit(STscObj* taos);
 int stmtClose(TAOS_STMT *stmt);
 int stmtExec(TAOS_STMT *stmt);
 const char *stmtErrstr(TAOS_STMT *stmt);
diff --git a/source/client/src/clientHb.c b/source/client/src/clientHb.c
index e1118833816bb405bdc123d15ed53b6b7eb9b29d..3ea40627a185d4a3ae92179f3ec1854c6c1ee6ee 100644
--- a/source/client/src/clientHb.c
+++ b/source/client/src/clientHb.c
@@ -174,7 +174,7 @@ static int32_t hbQueryHbRspHandle(SAppHbMgr *pAppHbMgr, SClientHbRsp *pRsp) {
       }
 
       if (pRsp->query->killConnection) {
-        taos_close(pTscObj);
+        taos_close_internal(pTscObj);
       }
 
       if (pRsp->query->pQnodeList) {
@@ -310,11 +310,12 @@ int32_t hbBuildQueryDesc(SQueryHbReqBasic *hbBasic, STscObj *pObj) {
     }
 
     tstrncpy(desc.sql, pRequest->sqlstr, sizeof(desc.sql));
-    desc.stime = pRequest->metric.start;
+    desc.stime = pRequest->metric.start / 1000;
     desc.queryId = pRequest->requestId;
     desc.useconds = now - pRequest->metric.start;
     desc.reqRid = pRequest->self;
     desc.pid = hbBasic->pid;
+    desc.stableQuery = pRequest->stableQuery;
     taosGetFqdn(desc.fqdn);
     desc.subPlanNum = pRequest->body.pDag ? pRequest->body.pDag->numOfSubplans : 0;
 
@@ -329,6 +330,7 @@ int32_t hbBuildQueryDesc(SQueryHbReqBasic *hbBasic, STscObj *pObj) {
       if (code) {
         taosArrayDestroy(desc.subDesc);
         desc.subDesc = NULL;
+        desc.subPlanNum = 0;
       }
     } else {
       desc.subDesc = NULL;
@@ -350,19 +352,24 @@ int32_t hbGetQueryBasicInfo(SClientHbKey *connKey, SClientHbReq *req) {
     return TSDB_CODE_QRY_APP_ERROR;
   }
 
-  int32_t numOfQueries = pTscObj->pRequests ? taosHashGetSize(pTscObj->pRequests) : 0;
-  if (numOfQueries <= 0) {
-    releaseTscObj(connKey->tscRid);
-    tscDebug("no queries on connection");
-    return TSDB_CODE_QRY_APP_ERROR;
-  }
-
   SQueryHbReqBasic *hbBasic = (SQueryHbReqBasic *)taosMemoryCalloc(1, sizeof(SQueryHbReqBasic));
   if (NULL == hbBasic) {
     tscError("calloc %d failed", (int32_t)sizeof(SQueryHbReqBasic));
     releaseTscObj(connKey->tscRid);
     return TSDB_CODE_QRY_OUT_OF_MEMORY;
   }
+  
+  hbBasic->connId = pTscObj->connId;
+  hbBasic->pid = taosGetPId();
+  taosGetAppName(hbBasic->app, NULL);
+
+  int32_t numOfQueries = pTscObj->pRequests ? taosHashGetSize(pTscObj->pRequests) : 0;
+  if (numOfQueries <= 0) {
+    req->query = hbBasic;
+    releaseTscObj(connKey->tscRid);
+    tscDebug("no queries on connection");
+    return TSDB_CODE_SUCCESS;
+  }
 
   hbBasic->queryDesc = taosArrayInit(numOfQueries, sizeof(SQueryDesc));
   if (NULL == hbBasic->queryDesc) {
@@ -372,9 +379,6 @@ int32_t hbGetQueryBasicInfo(SClientHbKey *connKey, SClientHbReq *req) {
     return TSDB_CODE_QRY_OUT_OF_MEMORY;
   }
 
-  hbBasic->connId = pTscObj->connId;
-  hbBasic->pid = taosGetPId();
-  taosGetAppName(hbBasic->app, NULL);
 
   int32_t code = hbBuildQueryDesc(hbBasic, pTscObj);
   if (code) {
diff --git a/source/client/src/clientImpl.c b/source/client/src/clientImpl.c
index 216aa5fbd01f517f4e1f0ec9f38440827e4be43c..949aa22cd1d0d56c2cd4a971385a5e88ac024393 100644
--- a/source/client/src/clientImpl.c
+++ b/source/client/src/clientImpl.c
@@ -58,7 +58,7 @@ static char* getClusterKey(const char* user, const char* auth, const char* ip, i
 static STscObj* taosConnectImpl(const char* user, const char* auth, const char* db, __taos_async_fn_t fp, void* param,
                                 SAppInstInfo* pAppInfo, int connType);
 
-TAOS* taos_connect_internal(const char* ip, const char* user, const char* pass, const char* auth, const char* db,
+STscObj* taos_connect_internal(const char* ip, const char* user, const char* pass, const char* auth, const char* db,
                             uint16_t port, int connType) {
   if (taos_init() != TSDB_CODE_SUCCESS) {
     return NULL;
@@ -697,6 +697,8 @@ SRequestObj* launchQuery(STscObj* pTscObj, const char* sql, int sqlLen) {
     return pRequest;
   }
 
+  pRequest->stableQuery = pQuery->stableQuery;
+
   return launchQueryImpl(pRequest, pQuery, false, NULL);
 }
 
@@ -923,7 +925,7 @@ STscObj* taosConnectImpl(const char* user, const char* auth, const char* db, __t
 
     terrno = pRequest->code;
     destroyRequest(pRequest);
-    taos_close(pTscObj);
+    taos_close_internal(pTscObj);
     pTscObj = NULL;
   } else {
     tscDebug("0x%" PRIx64 " connection is opening, connId:%u, dnodeConn:%p, reqId:0x%" PRIx64, pTscObj->id,
@@ -958,8 +960,8 @@ static SMsgSendInfo* buildConnectMsg(SRequestObj* pRequest) {
   taosMemoryFreeClear(db);
 
   connectReq.connType = pObj->connType;
-  connectReq.pid = htonl(appInfo.pid);
-  connectReq.startTime = htobe64(appInfo.startTime);
+  connectReq.pid = appInfo.pid;
+  connectReq.startTime = appInfo.startTime;
 
   tstrncpy(connectReq.app, appInfo.appName, sizeof(connectReq.app));
   tstrncpy(connectReq.user, pObj->user, sizeof(connectReq.user));
@@ -1088,7 +1090,12 @@ TAOS* taos_connect_auth(const char* ip, const char* user, const char* auth, cons
     return NULL;
   }
 
-  return taos_connect_internal(ip, user, NULL, auth, db, port, CONN_TYPE__QUERY);
+  STscObj* pObj = taos_connect_internal(ip, user, NULL, auth, db, port, CONN_TYPE__QUERY);
+  if (pObj) {
+    return (TAOS*)pObj->id;
+  }
+  
+  return (TAOS*)0;
 }
 
 TAOS* taos_connect_l(const char* ip, int ipLen, const char* user, int userLen, const char* pass, int passLen,
diff --git a/source/client/src/clientMain.c b/source/client/src/clientMain.c
index e3fafa0a8216db542ca3bc3d329f68e40af5206a..5f0dbdd41556d3347d963e29e57bf83d30ce8bee 100644
--- a/source/client/src/clientMain.c
+++ b/source/client/src/clientMain.c
@@ -93,10 +93,15 @@ TAOS *taos_connect(const char *ip, const char *user, const char *pass, const cha
     pass = TSDB_DEFAULT_PASS;
   }
 
-  return taos_connect_internal(ip, user, pass, NULL, db, port, CONN_TYPE__QUERY);
+  STscObj* pObj = taos_connect_internal(ip, user, pass, NULL, db, port, CONN_TYPE__QUERY);
+  if (pObj) {
+    return (TAOS*)pObj->id;
+  }
+  
+  return (TAOS*)0;
 }
 
-void taos_close(TAOS *taos) {
+void taos_close_internal(void *taos) {
   if (taos == NULL) {
     return;
   }
@@ -107,6 +112,17 @@ void taos_close(TAOS *taos) {
   taosRemoveRef(clientConnRefPool, pTscObj->id);
 }
 
+void taos_close(TAOS *taos) {
+  STscObj* pObj = acquireTscObj((int64_t)taos);
+  if (NULL == pObj) {
+    return;
+  }
+  
+  taos_close_internal(pObj);
+  releaseTscObj((int64_t)taos);
+}
+
+
 int taos_errno(TAOS_RES *tres) {
   if (tres == NULL) {
     return terrno;
@@ -186,29 +202,36 @@ static void syncQueryFn(void* param, void* res, int32_t code) {
 }
 
 TAOS_RES *taos_query(TAOS *taos, const char *sql) {
-  if (taos == NULL || sql == NULL) {
+  STscObj* pTscObj = acquireTscObj((int64_t)taos);
+  if (pTscObj == NULL || sql == NULL) {
+    terrno = TSDB_CODE_TSC_DISCONNECTED;
     return NULL;
   }
 
-  STscObj* pTscObj = (STscObj*)taos;
-
 #if SYNC_ON_TOP_OF_ASYNC
   SSyncQueryParam* param = taosMemoryCalloc(1, sizeof(SSyncQueryParam));
   tsem_init(&param->sem, 0, 0);
 
-  taos_query_a(pTscObj, sql, syncQueryFn, param);
+  taos_query_a(taos, sql, syncQueryFn, param);
   tsem_wait(&param->sem);
 
+  releaseTscObj((int64_t)taos);
+
   return param->pRequest;
 #else
   size_t sqlLen = strlen(sql);
   if (sqlLen > (size_t)TSDB_MAX_ALLOWED_SQL_LEN) {
+    releaseTscObj((int64_t)taos);
     tscError("sql string exceeds max length:%d", TSDB_MAX_ALLOWED_SQL_LEN);
     terrno = TSDB_CODE_TSC_EXCEED_SQL_LIMIT;
     return NULL;
   }
 
-  return execQuery(pTscObj, sql, sqlLen);
+  TAOS_RES* pRes = execQuery(pTscObj, sql, sqlLen);
+
+  releaseTscObj((int64_t)taos);
+
+  return pRes;
 #endif
 }
 
@@ -425,13 +448,15 @@ int taos_result_precision(TAOS_RES *res) {
 }
 
 int taos_select_db(TAOS *taos, const char *db) {
-  STscObj *pObj = (STscObj *)taos;
+  STscObj* pObj = acquireTscObj((int64_t)taos);
   if (pObj == NULL) {
+    releaseTscObj((int64_t)taos);
     terrno = TSDB_CODE_TSC_DISCONNECTED;
     return TSDB_CODE_TSC_DISCONNECTED;
   }
 
   if (db == NULL || strlen(db) == 0) {
+    releaseTscObj((int64_t)taos);
     terrno = TSDB_CODE_TSC_INVALID_INPUT;
     return terrno;
   }
@@ -443,6 +468,7 @@ int taos_select_db(TAOS *taos, const char *db) {
   int32_t   code = taos_errno(pRequest);
 
   taos_free_result(pRequest);
+  releaseTscObj((int64_t)taos);
   return code;
 }
 
@@ -589,19 +615,26 @@ int *taos_get_column_data_offset(TAOS_RES *res, int columnIndex) {
 int taos_validate_sql(TAOS *taos, const char *sql) { return true; }
 
 void taos_reset_current_db(TAOS *taos) {
-  if (taos == NULL) {
+  STscObj* pTscObj = acquireTscObj((int64_t)taos);
+  if (pTscObj == NULL) {
+    terrno = TSDB_CODE_TSC_DISCONNECTED;
     return;
   }
 
-  resetConnectDB(taos);
+  resetConnectDB(pTscObj);
+
+  releaseTscObj((int64_t)taos);
 }
 
 const char *taos_get_server_info(TAOS *taos) {
-  if (taos == NULL) {
+  STscObj* pTscObj = acquireTscObj((int64_t)taos);
+  if (pTscObj == NULL) {
+    terrno = TSDB_CODE_TSC_DISCONNECTED;
     return NULL;
   }
 
-  STscObj *pTscObj = (STscObj *)taos;
+  releaseTscObj((int64_t)taos);
+
   return pTscObj->ver;
 }
 
@@ -619,6 +652,7 @@ void retrieveMetaCallback(SMetaData* pResultMeta, void* param, int32_t code) {
 
   if (code == TSDB_CODE_SUCCESS) {
     code = qAnalyseSqlSemantic(pWrapper->pCtx, &pWrapper->catalogReq, pResultMeta, pQuery);
+    pRequest->stableQuery = pQuery->stableQuery;
   }
 
   if (code == TSDB_CODE_SUCCESS) {
@@ -652,10 +686,14 @@ void retrieveMetaCallback(SMetaData* pResultMeta, void* param, int32_t code) {
 }
 
 void taos_query_a(TAOS *taos, const char *sql, __taos_async_fn_t fp, void *param) {
-  ASSERT(fp != NULL);
-
-  if (taos == NULL || sql == NULL) {
+  STscObj* pTscObj = acquireTscObj((int64_t)taos);
+  if (pTscObj == NULL || sql == NULL || NULL == fp) {
     terrno = TSDB_CODE_INVALID_PARA;
+    if (pTscObj) {
+      releaseTscObj((int64_t)taos);
+    } else {
+      terrno = TSDB_CODE_TSC_DISCONNECTED;
+    }
     fp(param, NULL, terrno);
     return;
   }
@@ -670,7 +708,7 @@ void taos_query_a(TAOS *taos, const char *sql, __taos_async_fn_t fp, void *param
   }
 
   SRequestObj *pRequest = NULL;
-  int32_t code = buildRequest(taos, sql, sqlLen, &pRequest);
+  int32_t code = buildRequest(pTscObj, sql, sqlLen, &pRequest);
   if (code != TSDB_CODE_SUCCESS) {
     terrno = code;
     fp(param, NULL, terrno);
@@ -866,13 +904,18 @@ int taos_load_table_info(TAOS *taos, const char *tableNameList) {
 }
 
 TAOS_STMT *taos_stmt_init(TAOS *taos) {
-  if (taos == NULL) {
-    tscError("NULL parameter for %s", __FUNCTION__);
-    terrno = TSDB_CODE_INVALID_PARA;
+  STscObj* pObj = acquireTscObj((int64_t)taos);
+  if (NULL == pObj) {
+    tscError("invalid parameter for %s", __FUNCTION__);
+    terrno = TSDB_CODE_TSC_DISCONNECTED;
     return NULL;
   }
 
-  return stmtInit(taos);
+  TAOS_STMT* pStmt = stmtInit(pObj);
+  
+  releaseTscObj((int64_t)taos);
+
+  return pStmt;
 }
 
 int taos_stmt_prepare(TAOS_STMT *stmt, const char *sql, unsigned long length) {
diff --git a/source/client/src/clientSml.c b/source/client/src/clientSml.c
index 8c5645e5b605495c733e656c625a95fab02c27ad..274ae9984d60484c645be19ae2ee05f741aae3ca 100644
--- a/source/client/src/clientSml.c
+++ b/source/client/src/clientSml.c
@@ -1460,7 +1460,7 @@ static void smlDestroyInfo(SSmlHandle* info){
   taosMemoryFreeClear(info);
 }
 
-static SSmlHandle* smlBuildSmlInfo(TAOS* taos, SRequestObj* request, SMLProtocolType protocol, int8_t precision){
+static SSmlHandle* smlBuildSmlInfo(STscObj* pTscObj, SRequestObj* request, SMLProtocolType protocol, int8_t precision){
   int32_t code = TSDB_CODE_SUCCESS;
   SSmlHandle* info = (SSmlHandle*)taosMemoryCalloc(1, sizeof(SSmlHandle));
   if (NULL == info) {
@@ -1483,7 +1483,7 @@ static SSmlHandle* smlBuildSmlInfo(TAOS* taos, SRequestObj* request, SMLProtocol
   }
   ((SVnodeModifOpStmt*)(info->pQuery->pRoot))->payloadType = PAYLOAD_TYPE_KV;
 
-  info->taos        = (STscObj *)taos;
+  info->taos        = pTscObj;
   code = catalogGetHandle(info->taos->pAppInfo->clusterId, &info->pCatalog);
   if(code != TSDB_CODE_SUCCESS){
     uError("SML:0x%"PRIx64" get catalog error %d", info->id, code);
@@ -2447,13 +2447,21 @@ static void smlInsertCallback(void* param, void* res, int32_t code) {
  */
 
 TAOS_RES* taos_schemaless_insert(TAOS* taos, char* lines[], int numLines, int protocol, int precision) {
-  SRequestObj* request = (SRequestObj*)createRequest((STscObj *)taos, TSDB_SQL_INSERT);
+  STscObj* pTscObj = acquireTscObj((int64_t)taos);
+  if (NULL == pTscObj) {
+    terrno = TSDB_CODE_TSC_DISCONNECTED;
+    uError("SML:taos_schemaless_insert invalid taos");
+    return NULL;
+  }
+  
+  SRequestObj* request = (SRequestObj*)createRequest(pTscObj, TSDB_SQL_INSERT);
   if(!request){
+    releaseTscObj((int64_t)taos);
     uError("SML:taos_schemaless_insert error request is null");
     return NULL;
   }
 
-  ((STscObj *)taos)->schemalessType = 1;
+  pTscObj->schemalessType = 1;
   SSmlMsgBuf msg = {ERROR_MSG_BUF_DEFAULT_SIZE, request->msgBuf};
 
   int cnt = ceil(((double)numLines)/LINE_BATCH);
@@ -2468,7 +2476,7 @@ TAOS_RES* taos_schemaless_insert(TAOS* taos, char* lines[], int numLines, int pr
     goto end;
   }
 
-  if(isSchemalessDb(((STscObj *)taos), request) != TSDB_CODE_SUCCESS){
+  if(isSchemalessDb(pTscObj, request) != TSDB_CODE_SUCCESS){
     request->code = TSDB_CODE_SML_INVALID_DB_CONF;
     smlBuildInvalidDataMsg(&msg, "Cannot write data to a non schemaless database", NULL);
     goto end;
@@ -2493,13 +2501,13 @@ TAOS_RES* taos_schemaless_insert(TAOS* taos, char* lines[], int numLines, int pr
   }
 
   for (int i = 0; i < cnt; ++i) {
-    SRequestObj* req = (SRequestObj*)createRequest((STscObj *)taos, TSDB_SQL_INSERT);
+    SRequestObj* req = (SRequestObj*)createRequest(pTscObj, TSDB_SQL_INSERT);
     if(!req){
       request->code = TSDB_CODE_OUT_OF_MEMORY;
       uError("SML:taos_schemaless_insert error request is null");
       goto end;
     }
-    SSmlHandle* info = smlBuildSmlInfo(taos, req, (SMLProtocolType)protocol, precision);
+    SSmlHandle* info = smlBuildSmlInfo(pTscObj, req, (SMLProtocolType)protocol, precision);
     if(!info){
       request->code = TSDB_CODE_OUT_OF_MEMORY;
       uError("SML:taos_schemaless_insert error SSmlHandle is null");
@@ -2533,8 +2541,9 @@ end:
   taosThreadSpinDestroy(&params.lock);
   tsem_destroy(&params.sem);
 //  ((STscObj *)taos)->schemalessType = 0;
-  ((STscObj *)taos)->schemalessType = 1;
+  pTscObj->schemalessType = 1;
   uDebug("resultend:%s", request->msgBuf);
+  releaseTscObj((int64_t)taos);
   return (TAOS_RES*)request;
 }
 
diff --git a/source/client/src/clientStmt.c b/source/client/src/clientStmt.c
index 7dfb6505e9f27eb02d9dcf1eb16d85e004c0769d..1c0caec8102b5b0311c4cfd7240ea78270163628 100644
--- a/source/client/src/clientStmt.c
+++ b/source/client/src/clientStmt.c
@@ -478,7 +478,7 @@ int32_t stmtResetStmt(STscStmt* pStmt) {
   return TSDB_CODE_SUCCESS;
 }
 
-TAOS_STMT* stmtInit(TAOS* taos) {
+TAOS_STMT* stmtInit(STscObj* taos) {
   STscObj*  pObj = (STscObj*)taos;
   STscStmt* pStmt = NULL;
 
diff --git a/source/common/src/systable.c b/source/common/src/systable.c
index 0c35f5691e080c6c62840ed0d340df75f3c7b89e..98e16a05a6b2ea1bcbbcaf5259141f8fe5f41e4a 100644
--- a/source/common/src/systable.c
+++ b/source/common/src/systable.c
@@ -253,8 +253,8 @@ static const SSysTableMeta infosMeta[] = {
 static const SSysDbTableSchema connectionsSchema[] = {
     {.name = "conn_id", .bytes = 4, .type = TSDB_DATA_TYPE_UINT},
     {.name = "user", .bytes = TSDB_USER_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_BINARY},
-    {.name = "program", .bytes = TSDB_APP_NAME_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_BINARY},
-    {.name = "pid", .bytes = 4, .type = TSDB_DATA_TYPE_INT},
+    {.name = "app", .bytes = TSDB_APP_NAME_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_BINARY},
+    {.name = "pid", .bytes = 4, .type = TSDB_DATA_TYPE_UINT},
     {.name = "end_point", .bytes = TSDB_EP_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_BINARY},
     {.name = "login_time", .bytes = 8, .type = TSDB_DATA_TYPE_TIMESTAMP},
     {.name = "last_access", .bytes = 8, .type = TSDB_DATA_TYPE_TIMESTAMP},
@@ -298,19 +298,18 @@ static const SSysDbTableSchema offsetSchema[] = {
 };
 
 static const SSysDbTableSchema querySchema[] = {
-    {.name = "query_id", .bytes = 8, .type = TSDB_DATA_TYPE_UBIGINT},
+    {.name = "query_id", .bytes = 26 + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR},
+    {.name = "req_id", .bytes = 8, .type = TSDB_DATA_TYPE_UBIGINT},
     {.name = "connId", .bytes = 4, .type = TSDB_DATA_TYPE_UINT},
+    {.name = "app", .bytes = TSDB_APP_NAME_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR},    
+    {.name = "pid", .bytes = 4, .type = TSDB_DATA_TYPE_INT},
     {.name = "user", .bytes = TSDB_USER_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR},
     {.name = "end_point", .bytes = TSDB_IPv4ADDR_LEN + 6 + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR},
-    {.name = "qid", .bytes = 22 + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR},
     {.name = "create_time", .bytes = 8, .type = TSDB_DATA_TYPE_TIMESTAMP},
-    {.name = "time", .bytes = 8, .type = TSDB_DATA_TYPE_BIGINT},
-    {.name = "sql_obj_id", .bytes = QUERY_OBJ_ID_SIZE + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR},
-    {.name = "pid", .bytes = 4, .type = TSDB_DATA_TYPE_INT},
-    {.name = "ep", .bytes = TSDB_EP_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR},
+    {.name = "exec_usec", .bytes = 8, .type = TSDB_DATA_TYPE_BIGINT},
     {.name = "stable_query", .bytes = 1, .type = TSDB_DATA_TYPE_BOOL},
-    {.name = "sub_queries", .bytes = 4, .type = TSDB_DATA_TYPE_INT},
-    {.name = "sub_query_info", .bytes = TSDB_SHOW_SUBQUERY_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR},
+    {.name = "sub_num", .bytes = 4, .type = TSDB_DATA_TYPE_INT},
+    {.name = "sub_status", .bytes = TSDB_SHOW_SUBQUERY_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR},
     {.name = "sql", .bytes = TSDB_SHOW_SQL_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR},
 };
 
diff --git a/source/common/src/tmsg.c b/source/common/src/tmsg.c
index 31b8eb71bf26184bd351ca6d9b1a704f4bfc36c2..73fd0e7e71aa4291cd93efcd39d177eac6873ccf 100644
--- a/source/common/src/tmsg.c
+++ b/source/common/src/tmsg.c
@@ -210,6 +210,7 @@ static int32_t tSerializeSClientHbReq(SEncoder *pEncoder, const SClientHbReq *pR
         if (tEncodeI64(pEncoder, desc->stime) < 0) return -1;
         if (tEncodeI64(pEncoder, desc->reqRid) < 0) return -1;
         if (tEncodeI32(pEncoder, desc->pid) < 0) return -1;
+        if (tEncodeI8(pEncoder, desc->stableQuery) < 0) return -1;
         if (tEncodeCStr(pEncoder, desc->fqdn) < 0) return -1;
         if (tEncodeI32(pEncoder, desc->subPlanNum) < 0) return -1;
 
@@ -218,7 +219,7 @@ static int32_t tSerializeSClientHbReq(SEncoder *pEncoder, const SClientHbReq *pR
         for (int32_t m = 0; m < snum; ++m) {
           SQuerySubDesc *sDesc = taosArrayGet(desc->subDesc, m);
           if (tEncodeI64(pEncoder, sDesc->tid) < 0) return -1;
-          if (tEncodeI32(pEncoder, sDesc->status) < 0) return -1;
+          if (tEncodeCStr(pEncoder, sDesc->status) < 0) return -1;
         }
       }
     } else {
@@ -265,6 +266,7 @@ static int32_t tDeserializeSClientHbReq(SDecoder *pDecoder, SClientHbReq *pReq)
           if (tDecodeI64(pDecoder, &desc.stime) < 0) return -1;
           if (tDecodeI64(pDecoder, &desc.reqRid) < 0) return -1;
           if (tDecodeI32(pDecoder, &desc.pid) < 0) return -1;
+          if (tDecodeI8(pDecoder, (int8_t*)&desc.stableQuery) < 0) return -1;
           if (tDecodeCStrTo(pDecoder, desc.fqdn) < 0) return -1;
           if (tDecodeI32(pDecoder, &desc.subPlanNum) < 0) return -1;
 
@@ -277,7 +279,7 @@ static int32_t tDeserializeSClientHbReq(SDecoder *pDecoder, SClientHbReq *pReq)
             for (int32_t m = 0; m < snum; ++m) {
               SQuerySubDesc sDesc = {0};
               if (tDecodeI64(pDecoder, &sDesc.tid) < 0) return -1;
-              if (tDecodeI32(pDecoder, &sDesc.status) < 0) return -1;
+              if (tDecodeCStrTo(pDecoder, sDesc.status) < 0) return -1;
               taosArrayPush(desc.subDesc, &sDesc);
             }
           }
diff --git a/source/dnode/mnode/impl/src/mndProfile.c b/source/dnode/mnode/impl/src/mndProfile.c
index 28364737938587012902ca837b2c401d90cbdc83..ba09a182bb355ab12cdcdc3fb35d4a9b5621882b 100644
--- a/source/dnode/mnode/impl/src/mndProfile.c
+++ b/source/dnode/mnode/impl/src/mndProfile.c
@@ -39,6 +39,7 @@ typedef struct {
   int64_t  lastAccessTimeMs;
   uint64_t killId;
   int32_t  numOfQueries;
+  SRWLatch queryLock;
   SArray  *pQueries;  // SArray<SQueryDesc>
 } SConnObj;
 
@@ -53,8 +54,8 @@ static int32_t   mndProcessHeartBeatReq(SRpcMsg *pReq);
 static int32_t   mndProcessConnectReq(SRpcMsg *pReq);
 static int32_t   mndProcessKillQueryReq(SRpcMsg *pReq);
 static int32_t   mndProcessKillConnReq(SRpcMsg *pReq);
-static int32_t   mndRetrieveConns(SRpcMsg *pReq, SShowObj *pShow, char *data, int32_t rows);
-static int32_t   mndRetrieveQueries(SRpcMsg *pReq, SShowObj *pShow, char *data, int32_t rows);
+static int32_t   mndRetrieveConns(SRpcMsg *pReq, SShowObj *pShow, SSDataBlock *pBlock, int32_t rows);
+static int32_t   mndRetrieveQueries(SRpcMsg *pReq, SShowObj *pShow, SSDataBlock *pBlock, int32_t rows);
 static void      mndCancelGetNextQuery(SMnode *pMnode, void *pIter);
 
 int32_t mndInitProfile(SMnode *pMnode) {
@@ -74,7 +75,7 @@ int32_t mndInitProfile(SMnode *pMnode) {
   mndSetMsgHandle(pMnode, TDMT_MND_KILL_QUERY, mndProcessKillQueryReq);
   mndSetMsgHandle(pMnode, TDMT_MND_KILL_CONN, mndProcessKillConnReq);
 
-  //  mndAddShowRetrieveHandle(pMnode, TSDB_MGMT_TABLE_CONNS, mndRetrieveConns);
+  mndAddShowRetrieveHandle(pMnode, TSDB_MGMT_TABLE_CONNS, mndRetrieveConns);
   mndAddShowFreeIterHandle(pMnode, TSDB_MGMT_TABLE_CONNS, mndCancelGetNextConn);
   mndAddShowRetrieveHandle(pMnode, TSDB_MGMT_TABLE_QUERIES, mndRetrieveQueries);
   mndAddShowFreeIterHandle(pMnode, TSDB_MGMT_TABLE_QUERIES, mndCancelGetNextQuery);
@@ -129,7 +130,9 @@ static SConnObj *mndCreateConn(SMnode *pMnode, const char *user, int8_t connType
 }
 
 static void mndFreeConn(SConnObj *pConn) {
+  taosWLockLatch(&pConn->queryLock);
   taosArrayDestroyEx(pConn->pQueries, tFreeClientHbQueryDesc);
+  taosWUnLockLatch(&pConn->queryLock);
   
   mTrace("conn:%u, is destroyed, data:%p", pConn->id, pConn);
 }
@@ -222,8 +225,6 @@ static int32_t mndProcessConnectReq(SRpcMsg *pReq) {
     goto CONN_OVER;
   }
 
-  mndAcquireConn(pMnode, pConn->id);
-
   SConnectRsp connectRsp = {0};
   connectRsp.acctId = pUser->acctId;
   connectRsp.superUser = pUser->superUser;
@@ -259,12 +260,17 @@ CONN_OVER:
 }
 
 static int32_t mndSaveQueryList(SConnObj *pConn, SQueryHbReqBasic *pBasic) {
+  taosWLockLatch(&pConn->queryLock);
+
   taosArrayDestroyEx(pConn->pQueries, tFreeClientHbQueryDesc);
 
   pConn->pQueries = pBasic->queryDesc;
+  pConn->numOfQueries = pBasic->queryDesc ? taosArrayGetSize(pBasic->queryDesc) : 0;
   pBasic->queryDesc = NULL;
 
-  pConn->numOfQueries = pBasic->queryDesc ? taosArrayGetSize(pBasic->queryDesc) : 0;
+  mDebug("queries updated in conn %d, num:%d", pConn->id, pConn->numOfQueries);
+
+  taosWUnLockLatch(&pConn->queryLock);
 
   return TSDB_CODE_SUCCESS;
 }
@@ -353,14 +359,10 @@ static int32_t mndProcessQueryHeartBeat(SMnode *pMnode, SRpcMsg *pMsg, SClientHb
         return -1;
       } else {
         mDebug("user:%s, conn:%u is freed and create a new conn:%u", connInfo.user, pBasic->connId, pConn->id);
+        pConn = mndAcquireConn(pMnode, pBasic->connId);
       }
-    } else if (pConn->killed) {
-      mError("user:%s, conn:%u is already killed", connInfo.user, pConn->id);
-      mndReleaseConn(pMnode, pConn);
-      terrno = TSDB_CODE_MND_INVALID_CONNECTION;
-      return -1;
     }
-
+    
     SQueryHbRspBasic *rspBasic = taosMemoryCalloc(1, sizeof(SQueryHbRspBasic));
     if (rspBasic == NULL) {
       mndReleaseConn(pMnode, pConn);
@@ -389,6 +391,8 @@ static int32_t mndProcessQueryHeartBeat(SMnode *pMnode, SRpcMsg *pMsg, SClientHb
     mndReleaseConn(pMnode, pConn);
 
     hbRsp.query = rspBasic;
+  } else {
+    mDebug("no query info in hb msg");
   }
 
   int32_t kvNum = taosHashGetSize(pHbReq->info);
@@ -559,14 +563,13 @@ static int32_t mndProcessKillConnReq(SRpcMsg *pReq) {
   }
 }
 
-static int32_t mndRetrieveConns(SRpcMsg *pReq, SShowObj *pShow, char *data, int32_t rows) {
-  SMnode   *pMnode = pReq->info.node;
-  int32_t   numOfRows = 0;
-  SConnObj *pConn = NULL;
-  int32_t   cols = 0;
-  char     *pWrite;
-  char      ipStr[TSDB_IPv4ADDR_LEN + 6];
-
+static int32_t mndRetrieveConns(SRpcMsg *pReq, SShowObj *pShow, SSDataBlock *pBlock, int32_t rows) {
+  SMnode    *pMnode = pReq->info.node;
+  SSdb      *pSdb = pMnode->pSdb;
+  int32_t    numOfRows = 0;
+  int32_t    cols = 0;
+  SConnObj  *pConn = NULL;
+  
   if (pShow->pIter == NULL) {
     SProfileMgmt *pMgmt = &pMnode->profileMgmt;
     pShow->pIter = taosCacheCreateIter(pMgmt->cache);
@@ -574,48 +577,45 @@ static int32_t mndRetrieveConns(SRpcMsg *pReq, SShowObj *pShow, char *data, int3
 
   while (numOfRows < rows) {
     pConn = mndGetNextConn(pMnode, pShow->pIter);
-    if (pConn == NULL) break;
+    if (pConn == NULL) {
+      pShow->pIter = NULL;
+      break;
+    }
 
     cols = 0;
-#if 0
-    pWrite = data + pShow->offset[cols] * rows + pShow->pMeta->pSchemas[cols].bytes * numOfRows;
-    *(uint32_t *)pWrite = pConn->id;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->pMeta->pSchemas[cols].bytes * numOfRows;
-    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, pConn->user, pShow->pMeta->pSchemas[cols].bytes);
-    cols++;
-
-    // app name
-    pWrite = data + pShow->offset[cols] * rows + pShow->pMeta->pSchemas[cols].bytes * numOfRows;
-    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, pConn->app, pShow->pMeta->pSchemas[cols].bytes);
-    cols++;
-
-    // app pid
-    pWrite = data + pShow->offset[cols] * rows + pShow->pMeta->pSchemas[cols].bytes * numOfRows;
-    *(int32_t *)pWrite = pConn->pid;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->pMeta->pSchemas[cols].bytes * numOfRows;
-    taosIpPort2String(pConn->ip, pConn->port, ipStr);
-    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, ipStr, pShow->pMeta->pSchemas[cols].bytes);
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->pMeta->pSchemas[cols].bytes * numOfRows;
-    *(int64_t *)pWrite = pConn->loginTimeMs;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->pMeta->pSchemas[cols].bytes * numOfRows;
-    if (pConn->lastAccessTimeMs < pConn->loginTimeMs) pConn->lastAccessTimeMs = pConn->loginTimeMs;
-    *(int64_t *)pWrite = pConn->lastAccessTimeMs;
-    cols++;
-#endif
+
+    SColumnInfoData *pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+    colDataAppend(pColInfo, numOfRows, (const char *)&pConn->id, false);
+
+    char user[TSDB_USER_LEN + VARSTR_HEADER_SIZE] = {0};
+    STR_TO_VARSTR(user, pConn->user);
+    pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+    colDataAppend(pColInfo, numOfRows, (const char *)user, false);
+
+    char app[TSDB_APP_NAME_LEN + VARSTR_HEADER_SIZE];
+    STR_TO_VARSTR(app, pConn->app);
+    pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+    colDataAppend(pColInfo, numOfRows, (const char *)app, false);
+
+    pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+    colDataAppend(pColInfo, numOfRows, (const char *)&pConn->pid, false);
+
+    char endpoint[TSDB_IPv4ADDR_LEN + 6 + VARSTR_HEADER_SIZE] = {0};
+    sprintf(&endpoint[VARSTR_HEADER_SIZE], "%s:%d", taosIpStr(pConn->ip), pConn->port);
+    varDataLen(endpoint) = strlen(&endpoint[VARSTR_HEADER_SIZE]);
+    pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+    colDataAppend(pColInfo, numOfRows, (const char *)endpoint, false);
+
+    pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+    colDataAppend(pColInfo, numOfRows, (const char *)&pConn->loginTimeMs, false);
+
+    pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+    colDataAppend(pColInfo, numOfRows, (const char *)&pConn->lastAccessTimeMs, false);
 
     numOfRows++;
   }
 
   pShow->numOfRows += numOfRows;
-
   return numOfRows;
 }
 
@@ -633,9 +633,14 @@ static int32_t mndRetrieveQueries(SRpcMsg *pReq, SShowObj *pShow, SSDataBlock *p
 
   while (numOfRows < rows) {
     pConn = mndGetNextConn(pMnode, pShow->pIter);
-    if (pConn == NULL) break;
+    if (pConn == NULL) {
+      pShow->pIter = NULL;
+      break;
+    }
 
+    taosRLockLatch(&pConn->queryLock);
     if (NULL == pConn->pQueries || taosArrayGetSize(pConn->pQueries) <= 0) {
+      taosRUnLockLatch(&pConn->queryLock);
       continue;
     }
 
@@ -644,14 +649,28 @@ static int32_t mndRetrieveQueries(SRpcMsg *pReq, SShowObj *pShow, SSDataBlock *p
       SQueryDesc* pQuery = taosArrayGet(pConn->pQueries, i);
       cols = 0;
 
+      char queryId[26 + VARSTR_HEADER_SIZE] = {0};
+      sprintf(&queryId[VARSTR_HEADER_SIZE], "%x:%" PRIx64, pConn->id, pQuery->reqRid);
+      varDataLen(queryId) = strlen(&queryId[VARSTR_HEADER_SIZE]);
       SColumnInfoData *pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+      colDataAppend(pColInfo, numOfRows, (const char *)queryId, false);
+
+      pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
       colDataAppend(pColInfo, numOfRows, (const char *)&pQuery->queryId, false);
 
       pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
       colDataAppend(pColInfo, numOfRows, (const char *)&pConn->id, false);
 
+      char app[TSDB_APP_NAME_LEN + VARSTR_HEADER_SIZE];
+      STR_TO_VARSTR(app, pConn->app);
+      pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+      colDataAppend(pColInfo, numOfRows, (const char *)app, false);
+
+      pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+      colDataAppend(pColInfo, numOfRows, (const char *)&pQuery->pid, false);
+
       char user[TSDB_USER_LEN + VARSTR_HEADER_SIZE] = {0};
-      STR_TO_VARSTR(b1, pConn->user);
+      STR_TO_VARSTR(user, pConn->user);
       pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
       colDataAppend(pColInfo, numOfRows, (const char *)user, false);
 
@@ -661,23 +680,41 @@ static int32_t mndRetrieveQueries(SRpcMsg *pReq, SShowObj *pShow, SSDataBlock *p
       pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
       colDataAppend(pColInfo, numOfRows, (const char *)endpoint, false);
 
-      char b1[9] = {0};
-      STR_TO_VARSTR(b1, online ? "ready" : "offline");
       pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
-      colDataAppend(pColInfo, numOfRows, b1, false);
+      colDataAppend(pColInfo, numOfRows, (const char *)&pQuery->stime, false);
 
       pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
-      colDataAppend(pColInfo, numOfRows, (const char *)&pDnode->createdTime, false);
+      colDataAppend(pColInfo, numOfRows, (const char *)&pQuery->useconds, false);
 
-      char b[tListLen(offlineReason) + VARSTR_HEADER_SIZE] = {0};
-      STR_TO_VARSTR(b, online ? "" : offlineReason[pDnode->offlineReason]);
+      pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+      colDataAppend(pColInfo, numOfRows, (const char *)&pQuery->stableQuery, false);
 
       pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
-      colDataAppend(pColInfo, numOfRows, b, false);
+      colDataAppend(pColInfo, numOfRows, (const char *)&pQuery->subPlanNum, false);
+
+      char subStatus[TSDB_SHOW_SUBQUERY_LEN + VARSTR_HEADER_SIZE] = {0};
+      int32_t strSize = sizeof(subStatus);
+      int32_t offset = VARSTR_HEADER_SIZE;
+      for (int32_t i = 0; i < pQuery->subPlanNum && offset < strSize; ++i) {
+        if (i) {
+          offset += snprintf(subStatus + offset, strSize - offset - 1, ",");
+        }
+        SQuerySubDesc* pDesc = taosArrayGet(pQuery->subDesc, i);
+        offset += snprintf(subStatus + offset, strSize - offset - 1, "%" PRIu64 ":%s", pDesc->tid, pDesc->status);
+      }
+      varDataLen(subStatus) = strlen(&subStatus[VARSTR_HEADER_SIZE]);
+      pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+      colDataAppend(pColInfo, numOfRows, subStatus, false);
+
+      char sql[TSDB_SHOW_SQL_LEN + VARSTR_HEADER_SIZE] = {0};
+      STR_TO_VARSTR(sql, pQuery->sql);
+      pColInfo = taosArrayGet(pBlock->pDataBlock, cols++);
+      colDataAppend(pColInfo, numOfRows, (const char *)sql, false);
 
       numOfRows++;
-      sdbRelease(pSdb, pDnode);
     }
+    
+    taosRUnLockLatch(&pConn->queryLock);
   }
 
   pShow->numOfRows += numOfRows;
diff --git a/source/libs/function/src/udfd.c b/source/libs/function/src/udfd.c
index 02c485fa837bf4b487c4fdbd099171ead448c7f0..7fffa84e0b4ef85b846259a5173d9d2a263b143c 100644
--- a/source/libs/function/src/udfd.c
+++ b/source/libs/function/src/udfd.c
@@ -468,8 +468,8 @@ int32_t udfdConnectToMnode() {
   char pass[TSDB_PASSWORD_LEN + 1] = {0};
   taosEncryptPass_c((uint8_t *)(TSDB_DEFAULT_PASS), strlen(TSDB_DEFAULT_PASS), pass);
   tstrncpy(connReq.passwd, pass, sizeof(connReq.passwd));
-  connReq.pid = htonl(taosGetPId());
-  connReq.startTime = htobe64(taosGetTimestampMs());
+  connReq.pid = taosGetPId();
+  connReq.startTime = taosGetTimestampMs();
 
   int32_t contLen = tSerializeSConnectReq(NULL, 0, &connReq);
   void *  pReq = rpcMallocCont(contLen);
diff --git a/source/libs/nodes/src/nodesUtilFuncs.c b/source/libs/nodes/src/nodesUtilFuncs.c
index 1ea9124839195904073312df2fd8b0161f2bfed0..6db824e44586e186efa0f153045081e53b771ce1 100644
--- a/source/libs/nodes/src/nodesUtilFuncs.c
+++ b/source/libs/nodes/src/nodesUtilFuncs.c
@@ -199,6 +199,7 @@ SNodeptr nodesMakeNode(ENodeType type) {
     case QUERY_NODE_SHOW_SUBSCRIBES_STMT:
     case QUERY_NODE_SHOW_SMAS_STMT:
     case QUERY_NODE_SHOW_CONFIGS_STMT:
+    case QUERY_NODE_SHOW_CONNECTIONS_STMT:
     case QUERY_NODE_SHOW_QUERIES_STMT:
     case QUERY_NODE_SHOW_VNODES_STMT:
     case QUERY_NODE_SHOW_APPS_STMT:
diff --git a/source/libs/parser/src/parAstParser.c b/source/libs/parser/src/parAstParser.c
index aca7d9c9d332bc6318a39d457a406180ed1ee609..af22d8f62923534af95973b4425cbbdde726194a 100644
--- a/source/libs/parser/src/parAstParser.c
+++ b/source/libs/parser/src/parAstParser.c
@@ -383,6 +383,16 @@ static int32_t collectMetaKeyFromShowTopics(SCollectMetaKeyCxt* pCxt, SShowStmt*
                                  pCxt->pMetaCache);
 }
 
+static int32_t collectMetaKeyFromShowConnections(SCollectMetaKeyCxt* pCxt, SShowStmt* pStmt) {
+  return reserveTableMetaInCache(pCxt->pParseCxt->acctId, TSDB_PERFORMANCE_SCHEMA_DB, TSDB_PERFS_TABLE_CONNECTIONS,
+                                 pCxt->pMetaCache);
+}
+
+static int32_t collectMetaKeyFromShowQueries(SCollectMetaKeyCxt* pCxt, SShowStmt* pStmt) {
+  return reserveTableMetaInCache(pCxt->pParseCxt->acctId, TSDB_PERFORMANCE_SCHEMA_DB, TSDB_PERFS_TABLE_QUERIES,
+                                 pCxt->pMetaCache);
+}
+
 static int32_t collectMetaKeyFromShowTransactions(SCollectMetaKeyCxt* pCxt, SShowStmt* pStmt) {
   return reserveTableMetaInCache(pCxt->pParseCxt->acctId, TSDB_PERFORMANCE_SCHEMA_DB, TSDB_PERFS_TABLE_TRANS,
                                  pCxt->pMetaCache);
@@ -453,6 +463,10 @@ static int32_t collectMetaKeyFromQuery(SCollectMetaKeyCxt* pCxt, SNode* pStmt) {
       return collectMetaKeyFromShowVgroups(pCxt, (SShowStmt*)pStmt);
     case QUERY_NODE_SHOW_TOPICS_STMT:
       return collectMetaKeyFromShowTopics(pCxt, (SShowStmt*)pStmt);
+    case QUERY_NODE_SHOW_CONNECTIONS_STMT:
+      return collectMetaKeyFromShowConnections(pCxt, (SShowStmt*)pStmt);
+    case QUERY_NODE_SHOW_QUERIES_STMT:
+      return collectMetaKeyFromShowQueries(pCxt, (SShowStmt*)pStmt);
     case QUERY_NODE_SHOW_TRANSACTIONS_STMT:
       return collectMetaKeyFromShowTransactions(pCxt, (SShowStmt*)pStmt);
     case QUERY_NODE_DELETE_STMT:
diff --git a/source/libs/parser/src/parTranslater.c b/source/libs/parser/src/parTranslater.c
index d623b1a9a9c8ccf3cd42ab7c27abcd8563ddad7b..9e34fe6af7f9efbe8ead5d0595281e7379477327 100644
--- a/source/libs/parser/src/parTranslater.c
+++ b/source/libs/parser/src/parTranslater.c
@@ -42,6 +42,7 @@ typedef struct STranslateContext {
   SExplainOptions* pExplainOpt;
   SParseMetaCache* pMetaCache;
   bool             createStream;
+  bool             stableQuery;
 } STranslateContext;
 
 typedef struct SFullDatabaseName {
@@ -1478,6 +1479,9 @@ static int32_t translateTable(STranslateContext* pCxt, SNode* pTable) {
       if (TSDB_CODE_SUCCESS == code) {
         code = addNamespace(pCxt, pRealTable);
       }
+      if (TSDB_SUPER_TABLE == pRealTable->pMeta->tableType) {
+        pCxt->stableQuery = true;
+      }
       break;
     }
     case QUERY_NODE_TEMP_TABLE: {
@@ -4054,12 +4058,14 @@ static const char* getSysDbName(ENodeType type) {
     case QUERY_NODE_SHOW_SNODES_STMT:
     case QUERY_NODE_SHOW_LICENCE_STMT:
     case QUERY_NODE_SHOW_CLUSTER_STMT:
+    case QUERY_NODE_SHOW_VARIABLE_STMT:
       return TSDB_INFORMATION_SCHEMA_DB;
     case QUERY_NODE_SHOW_CONNECTIONS_STMT:
     case QUERY_NODE_SHOW_QUERIES_STMT:
     case QUERY_NODE_SHOW_TOPICS_STMT:
     case QUERY_NODE_SHOW_STREAMS_STMT:
     case QUERY_NODE_SHOW_TRANSACTIONS_STMT:
+    case QUERY_NODE_SHOW_APPS_STMT:
       return TSDB_PERFORMANCE_SCHEMA_DB;
     default:
       break;
@@ -4109,6 +4115,10 @@ static const char* getSysTableName(ENodeType type) {
       return TSDB_PERFS_TABLE_TOPICS;
     case QUERY_NODE_SHOW_TRANSACTIONS_STMT:
       return TSDB_PERFS_TABLE_TRANS;
+    case QUERY_NODE_SHOW_VARIABLE_STMT:
+      return TSDB_INS_TABLE_CONFIGS;
+    case QUERY_NODE_SHOW_APPS_STMT:
+      return TSDB_PERFS_TABLE_APPS;
     default:
       break;
   }
@@ -4714,6 +4724,7 @@ static int32_t buildDropTableVgroupHashmap(STranslateContext* pCxt, SDropTableCl
 
   if (TSDB_CODE_PAR_TABLE_NOT_EXIST == code && pClause->ignoreNotExists) {
     code = TSDB_CODE_SUCCESS;
+    goto over;
   }
 
   *pIsSuperTable = false;
@@ -4807,7 +4818,7 @@ static int32_t rewriteDropTable(STranslateContext* pCxt, SQuery* pQuery) {
     }
   }
 
-  if (isSuperTable) {
+  if (isSuperTable || 0 == taosHashGetSize(pVgroupHashmap)) {
     taosHashCleanup(pVgroupHashmap);
     return TSDB_CODE_SUCCESS;
   }
@@ -5152,6 +5163,8 @@ static int32_t rewriteQuery(STranslateContext* pCxt, SQuery* pQuery) {
     case QUERY_NODE_SHOW_CLUSTER_STMT:
     case QUERY_NODE_SHOW_TOPICS_STMT:
     case QUERY_NODE_SHOW_TRANSACTIONS_STMT:
+    case QUERY_NODE_SHOW_VARIABLE_STMT:
+    case QUERY_NODE_SHOW_APPS_STMT:
       code = rewriteShow(pCxt, pQuery);
       break;
     case QUERY_NODE_CREATE_TABLE_STMT:
@@ -5248,6 +5261,8 @@ static int32_t setQuery(STranslateContext* pCxt, SQuery* pQuery) {
       break;
   }
 
+  pQuery->stableQuery = pCxt->stableQuery;
+
   if (pQuery->haveResultSet) {
     if (TSDB_CODE_SUCCESS != extractResultSchema(pQuery->pRoot, &pQuery->numOfResCols, &pQuery->pResSchema)) {
       return TSDB_CODE_OUT_OF_MEMORY;
diff --git a/source/libs/scheduler/src/scheduler.c b/source/libs/scheduler/src/scheduler.c
index 18068870d772f96f89e274e093a33f0801fa9c05..0eaeeae9cb75edbe5c3b974af4acb61eee6e713d 100644
--- a/source/libs/scheduler/src/scheduler.c
+++ b/source/libs/scheduler/src/scheduler.c
@@ -151,7 +151,9 @@ int32_t schedulerGetTasksStatus(int64_t job, SArray *pSub) {
 
     for (int32_t m = 0; m < pLevel->taskNum; ++m) {
       SSchTask     *pTask = taosArrayGet(pLevel->subTasks, m);
-      SQuerySubDesc subDesc = {.tid = pTask->taskId, .status = pTask->status};
+      SQuerySubDesc subDesc = {0};
+      subDesc.tid = pTask->taskId;
+      strcpy(subDesc.status, jobTaskStatusStr(pTask->status));
 
       taosArrayPush(pSub, &subDesc);
     }
diff --git a/source/util/src/tcache.c b/source/util/src/tcache.c
index 10a54755559f60f80b0b3f5b64ddf1060de71c6c..5f9c2485d17a89a8a1046a0b48b1fd6276f5035c 100644
--- a/source/util/src/tcache.c
+++ b/source/util/src/tcache.c
@@ -931,15 +931,15 @@ bool taosCacheIterNext(SCacheIter *pIter) {
   SCacheObj *pCacheObj = pIter->pCacheObj;
 
   if (pIter->index + 1 >= pIter->numOfObj) {
-    if (pIter->entryIndex + 1 >= pCacheObj->capacity) {
-      return false;
-    }
-
     // release the reference for all objects in the snapshot
     for (int32_t i = 0; i < pIter->numOfObj; ++i) {
       char *p = pIter->pCurrent[i]->data;
       taosCacheRelease(pCacheObj, (void **)&p, false);
       pIter->pCurrent[i] = NULL;
+    }   
+
+    if (pIter->entryIndex + 1 >= pCacheObj->capacity) {
+      return false;
     }
 
     while (1) {