[TD-2332]<test>test diff&&top

tests/pytest/fulltest.sh

@@ -29,6 +29,7 @@ python3 ./test.py -f table/db_table.py
 python3 ./test.py -f table/create_sensitive.py
 #python3 ./test.py -f table/tablename-boundary.py
 python3 ./test.py  -f table/max_table_length.py
+python3 ./test.py -f query/bug2281.py
 
 # tag
 python3 ./test.py -f tag_lite/filter.py

tests/pytest/pytest_1.sh

@@ -160,6 +160,7 @@ python3 ./test.py -f query/bug1874.py
 python3 ./test.py -f query/bug1875.py
 python3 ./test.py -f query/bug1876.py
 python3 ./test.py -f query/bug2218.py 
+python3 ./test.py -f query/bug2281.py
 python3 bug2265.py
 #stream
 python3 ./test.py -f stream/metric_1.py

tests/pytest/query/bug2281.py

@@ -0,0 +1,47 @@
+###################################################################
+#           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
+from util.log import *
+from util.cases import *
+from util.sql import *
+from util.dnodes import *
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)
+
+    def run(self):
+        tdSql.prepare()
+        print("==========step1")
+        print("create table && insert data")
+        
+        tdSql.execute("create table t1 (ts timestamp, c1 int, c2 float)")
+        insertRows = 10
+        t0 = 1604298064000
+        tdLog.info("insert %d rows" % (insertRows))
+        for i in range(insertRows):
+            ret = tdSql.execute(
+                "insert into t1 values (%d , %d,%d)" %
+                (t0+i,i%100,i/2.0))
+
+        print("==========step2")
+        print("query diff && top")
+        tdSql.error('select diff(c1),top(c2) from t1')
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())