<test>fix test case error

tests/pytest/query/bug2117.py

+###################################################################
+#           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 mt0 (ts timestamp, c1 int, c2 float, c3 bigint, c4 smallint, c5 tinyint, c6 double, c7 bool,c8 binary(20),c9 nchar(20))")
+        insertRows = 1000
+        t0 = 1604298064000
+        tdLog.info("insert %d rows" % (insertRows))
+        for i in range(insertRows):
+            ret = tdSql.execute(
+                "insert into mt0 values (%d , %d,%d,%d,%d,%d,%d,%d,'%s','%s')" %
+                (t0+i,i%100,i/2,i%41,i%100,i%100,i*1.0,i%2,'taos'+str(i%100),'涛思'+str(i%100)))
+        print("==========step2")
+        print("test last with group by normal_col ")
+        tdSql.query('select last(c1) from mt0 group by c3')
+        tdSql.checkData(0,0,84)
+        tdSql.checkData(0,1,85)
+        
+
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
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