fix TD-1471

src/client/src/tscSql.c

@@ -479,8 +479,11 @@ TAOS_ROW taos_fetch_row(TAOS_RES *res) {
   SSqlCmd *pCmd = &pSql->cmd;
   SSqlRes *pRes = &pSql->res;
   
-  if (pRes->qhandle == 0 ||
-      pRes->code == TSDB_CODE_TSC_QUERY_CANCELLED ||
+  if (pRes->qhandle == 0) {
+    pRes->code = TSDB_CODE_TSC_INVALID_QHANDLE;
+    return NULL;
+  }
+  if (pRes->code == TSDB_CODE_TSC_QUERY_CANCELLED ||
       pCmd->command == TSDB_SQL_RETRIEVE_EMPTY_RESULT ||
       pCmd->command == TSDB_SQL_INSERT) {
     return NULL;

src/connector/python/linux/python2/taos/cursor.py

@@ -192,8 +192,10 @@ class TDengineCursor(object):
         buffer = [[] for i in range(len(self._fields))]
         self._rowcount = 0
         while True:
-            block, num_of_fields = CTaosInterface.fetchBlock(
-                self._result, self._fields)
+            block, num_of_fields = CTaosInterface.fetchBlock(self._result, self._fields)
+            errno = CTaosInterface.libtaos.taos_errno(self._result)
+            if errno != 0:
+                raise ProgrammingError(CTaosInterface.errStr(self._result), errno)
             if num_of_fields == 0:
                 break
             self._rowcount += num_of_fields

src/connector/python/linux/python3/taos/cursor.py

@@ -207,8 +207,10 @@ class TDengineCursor(object):
         buffer = [[] for i in range(len(self._fields))]
         self._rowcount = 0
         while True:
-            block, num_of_fields = CTaosInterface.fetchBlock(
-                self._result, self._fields)
+            block, num_of_fields = CTaosInterface.fetchBlock(self._result, self._fields)
+            errno = CTaosInterface.libtaos.taos_errno(self._result)
+            if errno != 0:
+                raise ProgrammingError(CTaosInterface.errStr(self._result), errno)
             if num_of_fields == 0:
                 break
             self._rowcount += num_of_fields

src/connector/python/windows/python2/taos/cursor.py

@@ -142,6 +142,9 @@ class TDengineCursor(object):
         self._rowcount = 0
         while True:
             block, num_of_fields = CTaosInterface.fetchBlock(self._result, self._fields)
+            errno = CTaosInterface.libtaos.taos_errno(self._result)
+            if errno != 0:
+                raise ProgrammingError(CTaosInterface.errStr(self._result), errno)
             if num_of_fields == 0: break
             self._rowcount += num_of_fields
             for i in range(len(self._fields)):

src/connector/python/windows/python3/taos/cursor.py

@@ -142,6 +142,9 @@ class TDengineCursor(object):
         self._rowcount = 0
         while True:
             block, num_of_fields = CTaosInterface.fetchBlock(self._result, self._fields)
+            errno = CTaosInterface.libtaos.taos_errno(self._result)
+            if errno != 0:
+                raise ProgrammingError(CTaosInterface.errStr(self._result), errno)
             if num_of_fields == 0: break
             self._rowcount += num_of_fields
             for i in range(len(self._fields)):

tests/pytest/fulltest.sh

@@ -149,6 +149,7 @@ python3 ./test.py -f query/queryNullValueTest.py
 python3 ./test.py -f query/queryInsertValue.py
 python3 ./test.py -f query/queryConnection.py
 python3 ./test.py -f query/natualInterval.py
+python3 ./test.py -f query/bug1471.py
 
 #stream
 python3 ./test.py -f stream/metric_1.py

tests/pytest/query/bug1471.py

@@ -0,0 +1,73 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import time
+import threading
+
+
+class myThread(threading.Thread):
+    def __init__(self, conn):
+        threading.Thread.__init__(self)
+        self.event = threading.Event()
+        self.conn = taos.connect(conn._host, port=conn._port, config=conn._config)
+
+    def run(self):
+        cur = self.conn.cursor()
+        self.event.wait()
+        cur.execute("drop database db")
+        cur.close()
+        self.conn.close()
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+    def run(self):
+        for i in range(50):
+            print("round", i)
+            thread = myThread(tdSql.cursor._connection)
+            thread.start()
+
+            tdSql.execute('reset query cache')
+            tdSql.execute('drop database if exists db')
+            tdSql.execute('create database db')
+            tdSql.execute('use db')
+            tdSql.execute("create table car (ts timestamp, s int)")
+            tdSql.execute("insert into car values('2020-10-19 17:00:00', 123)")
+
+            thread.event.set()
+            try:
+                tdSql.query("select s from car where ts = '2020-10-19 17:00:00'")
+            except Exception as e:
+                pass
+            else:
+                tdSql.checkData(0, 0, 123)
+
+            thread.join()
+            time.sleep(0.2)
+
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())