[TD-1245]<test> add test case for interval

tests/pytest/query/queryInterval.py

@@ -0,0 +1,51 @@
+###################################################################
+#           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 = 1538548685000
+
+    def run(self):
+        tdSql.prepare()
+
+        tdSql.execute("create table st (ts timestamp, voltage int) tags (loc nchar(30))")
+        tdSql.execute("insert into t0 using st tags('beijing') values(now, 220) (now - 15d, 221) (now - 30d, 225) (now - 35d, 228) (now - 45d, 222)" )
+
+        tdSql.query("select avg(voltage) from st interval(1n)")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 225.0)
+        tdSql.checkData(1, 1, 220.5)
+        
+        tdSql.query("select avg(voltage) from st interval(1n, 15d)")
+        tdSql.checkRows(3)
+        tdSql.checkData(0, 1, 225.0)
+        tdSql.checkData(1, 1, 223.0)
+        tdSql.checkData(2, 1, 220.0)
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())