[TD-1290]<test> add test case for group by

tests/pytest/query/queryGroupbySort.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
+import taos
+from util.log import tdLog
+from util.cases import tdCases
+from util.sql import tdSql
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)
+
+        self.ts = 1537146000000
+
+    def run(self):
+        tdSql.prepare()
+
+        tdSql.execute(
+            "create table stb(ts timestamp,i int) tags (p_id nchar(20));")
+        tdSql.execute(
+            "insert into tb using stb tags('11231') values (%d, %d) (%d, %d) (%d, %d) (%d, %d)" 
+            % (self.ts, 12, self.ts + 1, 15, self.ts + 2, 15, self.ts + 3, 12))
+
+        tdSql.query(''' select last(ts) p_time,i from stb where p_id='11231' and ts>=%d and ts <=%d 
+            group by i order by time desc limit 100 ''' % (self.ts, self.ts + 4))
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 0, "2018-09-17 09:00:00.003000")
+        tdSql.checkData(1, 0, "2018-09-17 09:00:00.002000")
+
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())

tests/pytest/util/sql.py

@@ -123,7 +123,7 @@ class TDSql:
 
     def checkData(self, row, col, data):
         self.checkRowCol(row, col) 
-        if self.queryResult[row][col] != data:            
+        if str(self.queryResult[row][col]) != str(data): 
             if isinstance(data, float) and abs(self.queryResult[row][col] - data) <= 0.000001:                
                 tdLog.info("sql:%s, row:%d col:%d data:%f == expect:%f" %
                             (self.sql, row, col, self.queryResult[row][col], data))