diff --git a/tests/pytest/fulltest.sh b/tests/pytest/fulltest.sh
index 9d1aef0dc5cc2cf266931ff6e8ba88794649686c..904e712fa46a9f409d8196759569b22c84a091b6 100755
--- a/tests/pytest/fulltest.sh
+++ b/tests/pytest/fulltest.sh
@@ -144,6 +144,7 @@ python3 ./test.py -f query/querySort.py
 python3 ./test.py -f query/queryJoin.py
 python3 ./test.py -f query/select_last_crash.py
 python3 ./test.py -f query/queryNullValueTest.py
+python3 ./test.py -f query/queryInsertValue.py
 
 #stream
 python3 ./test.py -f stream/metric_1.py
@@ -161,3 +162,22 @@ python3 ./test.py -f client/client.py
 # Misc
 python3 testCompress.py
 python3 testNoCompress.py
+
+# functions
+python3 ./test.py -f functions/function_avg.py
+python3 ./test.py -f functions/function_bottom.py
+python3 ./test.py -f functions/function_count.py
+python3 ./test.py -f functions/function_diff.py
+python3 ./test.py -f functions/function_first.py
+python3 ./test.py -f functions/function_last.py
+python3 ./test.py -f functions/function_last_row.py
+python3 ./test.py -f functions/function_leastsquares.py
+python3 ./test.py -f functions/function_max.py
+python3 ./test.py -f functions/function_min.py
+python3 ./test.py -f functions/function_operations.py
+python3 ./test.py -f functions/function_percentile.py
+python3 ./test.py -f functions/function_spread.py
+python3 ./test.py -f functions/function_stddev.py
+python3 ./test.py -f functions/function_sum.py
+python3 ./test.py -f functions/function_top.py
+python3 ./test.py -f functions/function_twa.py
\ No newline at end of file
diff --git a/tests/pytest/functions/function_avg.py b/tests/pytest/functions/function_avg.py
new file mode 100644
index 0000000000000000000000000000000000000000..9481550ba3f9d912b734d19b7c794c495fffdecd
--- /dev/null
+++ b/tests/pytest/functions/function_avg.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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # average verifacation 
+        tdSql.error("select avg(ts) from test")
+        tdSql.error("select avg(ts) from test1")
+        tdSql.error("select avg(col7) from test")
+        tdSql.error("select avg(col7) from test1")
+        tdSql.error("select avg(col8) from test")
+        tdSql.error("select avg(col8) from test1")
+        tdSql.error("select avg(col9) from test")
+        tdSql.error("select avg(col9) from test1")
+
+        tdSql.query("select avg(col1) from test")
+        tdSql.checkData(0, 0, np.average(intData))
+        tdSql.query("select avg(col2) from test")
+        tdSql.checkData(0, 0, np.average(intData))
+        tdSql.query("select avg(col3) from test")
+        tdSql.checkData(0, 0, np.average(intData))
+        tdSql.query("select avg(col4) from test")
+        tdSql.checkData(0, 0, np.average(intData))
+        tdSql.query("select avg(col5) from test")
+        tdSql.checkData(0, 0, np.average(floatData))              
+        tdSql.query("select avg(col6) from test")
+        tdSql.checkData(0, 0, np.average(floatData))              
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_bottom.py b/tests/pytest/functions/function_bottom.py
new file mode 100644
index 0000000000000000000000000000000000000000..cb008d522ab934adeb90415cd7a4b5e7c73957e7
--- /dev/null
+++ b/tests/pytest/functions/function_bottom.py
@@ -0,0 +1,98 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # bottom verifacation 
+        tdSql.error("select bottom(ts, 10) from test")
+        tdSql.error("select bottom(col1, 0) from test")
+        tdSql.error("select bottom(col1, 101) from test")
+        tdSql.error("select bottom(col2, 0) from test")
+        tdSql.error("select bottom(col2, 101) from test")
+        tdSql.error("select bottom(col3, 0) from test")
+        tdSql.error("select bottom(col3, 101) from test")
+        tdSql.error("select bottom(col4, 0) from test")
+        tdSql.error("select bottom(col4, 101) from test")
+        tdSql.error("select bottom(col5, 0) from test")
+        tdSql.error("select bottom(col5, 101) from test")
+        tdSql.error("select bottom(col6, 0) from test")
+        tdSql.error("select bottom(col6, 101) from test")        
+        tdSql.error("select bottom(col7, 10) from test")        
+        tdSql.error("select bottom(col8, 10) from test")
+        tdSql.error("select bottom(col9, 10) from test")
+
+        tdSql.query("select bottom(col1, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 1)
+        tdSql.checkData(1, 1, 2)
+
+        tdSql.query("select bottom(col2, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 1)
+        tdSql.checkData(1, 1, 2)
+
+        tdSql.query("select bottom(col3, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 1)
+        tdSql.checkData(1, 1, 2)
+
+        tdSql.query("select bottom(col4, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 1)
+        tdSql.checkData(1, 1, 2)
+
+        tdSql.query("select bottom(col5, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 0.1)
+        tdSql.checkData(1, 1, 1.1)
+
+        tdSql.query("select bottom(col6, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 0.1)
+        tdSql.checkData(1, 1, 1.1)
+                   
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_count.py b/tests/pytest/functions/function_count.py
new file mode 100644
index 0000000000000000000000000000000000000000..e5ef71bf5a79075367a054aa9bd5b7649caafe25
--- /dev/null
+++ b/tests/pytest/functions/function_count.py
@@ -0,0 +1,84 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                
+        
+        # Count verifacation
+        tdSql.query("select count(*) from test")        
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select count(ts) from test")        
+        tdSql.checkData(0, 0, 10)                        
+        tdSql.query("select count(col1) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col2) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col3) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col4) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col5) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col6) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col7) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col8) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col9) from test")        
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.execute("alter table test add column col10 int")
+        tdSql.query("select count(col10) from test")        
+        tdSql.checkRows(0)
+
+        tdSql.execute("insert into test1 values(now, 1, 2, 3, 4, 1.1, 2.2, false, 'test', 'test' 1)")
+        tdSql.query("select count(col10) from test")        
+        tdSql.checkData(0, 0, 1)        
+              
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_diff.py b/tests/pytest/functions/function_diff.py
new file mode 100644
index 0000000000000000000000000000000000000000..62daa5fa82ce05d5ae8ef467522aee651677c292
--- /dev/null
+++ b/tests/pytest/functions/function_diff.py
@@ -0,0 +1,103 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        tdSql.execute("insert into test1 values(%d, 0, 0, 0, 0, 0.0, 0.0, False, ' ', ' ')" % (self.ts - 1))
+        tdSql.query("select diff(col1) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select diff(col2) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select diff(col3) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select diff(col4) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select diff(col5) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select diff(col6) from test1")
+        tdSql.checkRows(0)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # diff verifacation 
+        tdSql.error("select diff(ts) from test")
+        tdSql.error("select diff(ts) from test1")
+        tdSql.error("select diff(col1) from test")
+        tdSql.error("select diff(col2) from test")
+        tdSql.error("select diff(col3) from test")
+        tdSql.error("select diff(col4) from test")
+        tdSql.error("select diff(col5) from test")
+        tdSql.error("select diff(col6) from test")
+        tdSql.error("select diff(col7) from test")     
+        tdSql.error("select diff(col7) from test1")               
+        tdSql.error("select diff(col8) from test") 
+        tdSql.error("select diff(col8) from test1")
+        tdSql.error("select diff(col9) from test")        
+        tdSql.error("select diff(col9) from test1")
+        
+        tdSql.query("select diff(col1) from test1")
+        tdSql.checkRows(10)
+
+        tdSql.query("select diff(col2) from test1")
+        tdSql.checkRows(10)
+
+        tdSql.query("select diff(col3) from test1")
+        tdSql.checkRows(10)
+
+        tdSql.query("select diff(col4) from test1")
+        tdSql.checkRows(10)
+
+        tdSql.query("select diff(col5) from test1")
+        tdSql.checkRows(10)
+
+        tdSql.query("select diff(col6) from test1")
+        tdSql.checkRows(10)
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_first.py b/tests/pytest/functions/function_first.py
new file mode 100644
index 0000000000000000000000000000000000000000..27ce09b309bbe3d65142eb78bc6bc3f97295aa3d
--- /dev/null
+++ b/tests/pytest/functions/function_first.py
@@ -0,0 +1,124 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        tdSql.execute("insert into test1(ts) values(%d)" % (self.ts - 1))
+
+        # first verifacation         
+        tdSql.query("select first(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, None)
+
+        tdSql.query("select first(col1) from test1")
+        tdSql.checkRows(0)        
+
+        tdSql.query("select first(col2) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col3) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col4) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col5) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col6) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col7) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col8) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col9) from test1")
+        tdSql.checkRows(0)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)  
+
+        tdSql.query("select first(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, 1)
+
+        tdSql.query("select first(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 1)
+
+        tdSql.query("select first(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 1)
+
+        tdSql.query("select first(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 1)
+
+        tdSql.query("select first(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 1)
+
+        tdSql.query("select first(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0.1)
+
+        tdSql.query("select first(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0.1)
+
+        tdSql.query("select first(col7) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, False)
+
+        tdSql.query("select first(col8) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'taosdata1')
+
+        tdSql.query("select first(col9) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, '涛思数据1')
+                
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_last.py b/tests/pytest/functions/function_last.py
new file mode 100644
index 0000000000000000000000000000000000000000..6412b7ce6a2f0d8d39f52c3856a504ad01dfa94d
--- /dev/null
+++ b/tests/pytest/functions/function_last.py
@@ -0,0 +1,124 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        tdSql.execute("insert into test1(ts) values(%d)" % (self.ts - 1))
+
+        # first verifacation         
+        tdSql.query("select last(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, None)
+
+        tdSql.query("select last(col1) from test1")
+        tdSql.checkRows(0)        
+
+        tdSql.query("select last(col2) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col3) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col4) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col5) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col6) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col7) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col8) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col9) from test1")
+        tdSql.checkRows(0)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)  
+
+        tdSql.query("select last(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, 10)
+
+        tdSql.query("select last(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+
+        tdSql.query("select last(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+
+        tdSql.query("select last(col7) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, True)
+
+        tdSql.query("select last(col8) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'taosdata10')
+
+        tdSql.query("select last(col9) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, '涛思数据10')
+                
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_last_row.py b/tests/pytest/functions/function_last_row.py
new file mode 100644
index 0000000000000000000000000000000000000000..19db865a3d929b8959da4eb72f87da9c9f552930
--- /dev/null
+++ b/tests/pytest/functions/function_last_row.py
@@ -0,0 +1,133 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        tdSql.execute("insert into test1(ts) values(%d)" % (self.ts - 1))
+
+        # first verifacation         
+        tdSql.query("select last_row(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, None)
+
+        tdSql.query("select last_row(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col7) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col8) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col9) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)  
+
+        tdSql.query("select last_row(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, 10)
+
+        tdSql.query("select last_row(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last_row(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last_row(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last_row(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last_row(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+
+        tdSql.query("select last_row(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+
+        tdSql.query("select last_row(col7) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, True)
+
+        tdSql.query("select last_row(col8) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'taosdata10')
+
+        tdSql.query("select last_row(col9) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, '涛思数据10')
+                
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_leastsquares.py b/tests/pytest/functions/function_leastsquares.py
new file mode 100644
index 0000000000000000000000000000000000000000..66187926f5c97d59710d57c7b60eb8149c3ed20f
--- /dev/null
+++ b/tests/pytest/functions/function_leastsquares.py
@@ -0,0 +1,82 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # leastsquares verifacation 
+        tdSql.error("select leastsquares(ts, 1, 1) from test1")
+        tdSql.error("select leastsquares(col1, 1, 1) from test")
+        tdSql.error("select leastsquares(col2, 1, 1) from test")
+        tdSql.error("select leastsquares(col3, 1, 1) from test")
+        tdSql.error("select leastsquares(col4, 1, 1) from test")
+        tdSql.error("select leastsquares(col5, 1, 1) from test")
+        tdSql.error("select leastsquares(col6, 1, 1) from test")
+        tdSql.error("select leastsquares(col7, 1, 1) from test1")
+        tdSql.error("select leastsquares(col8, 1, 1) from test1")
+        tdSql.error("select leastsquares(col9, 1, 1) from test1")
+                
+        tdSql.query("select leastsquares(col1, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:0.000000}')
+
+        tdSql.query("select leastsquares(col2, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:0.000000}')
+
+        tdSql.query("select leastsquares(col3, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:0.000000}')
+
+        tdSql.query("select leastsquares(col4, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:0.000000}')
+
+        tdSql.query("select leastsquares(col5, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:-0.900000}')
+
+        tdSql.query("select leastsquares(col6, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:-0.900000}')
+
+        
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_max.py b/tests/pytest/functions/function_max.py
new file mode 100644
index 0000000000000000000000000000000000000000..02364e0fded2e93a8ad0af7fb0f6ca92232a8322
--- /dev/null
+++ b/tests/pytest/functions/function_max.py
@@ -0,0 +1,78 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # min verifacation 
+        tdSql.error("select max(ts) from test")
+        tdSql.error("select max(ts) from test1")
+        tdSql.error("select max(col7) from test")
+        tdSql.error("select max(col7) from test1")
+        tdSql.error("select max(col8) from test")
+        tdSql.error("select max(col8) from test1")
+        tdSql.error("select max(col9) from test")
+        tdSql.error("select max(col9) from test1")
+        
+        tdSql.query("select max(col1) from test1")
+        tdSql.checkData(0, 0, np.max(intData))
+
+        tdSql.query("select max(col2) from test1")
+        tdSql.checkData(0, 0, np.max(intData))
+
+        tdSql.query("select max(col3) from test1")
+        tdSql.checkData(0, 0, np.max(intData))
+
+        tdSql.query("select max(col4) from test1")
+        tdSql.checkData(0, 0, np.max(intData))
+        
+        tdSql.query("select max(col5) from test1")
+        tdSql.checkData(0, 0, np.max(floatData))
+
+        tdSql.query("select max(col6) from test1")
+        tdSql.checkData(0, 0, np.max(floatData))
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_min.py b/tests/pytest/functions/function_min.py
new file mode 100644
index 0000000000000000000000000000000000000000..bc180bc22414a4a3aa3d233438b10a04fd08bc2b
--- /dev/null
+++ b/tests/pytest/functions/function_min.py
@@ -0,0 +1,78 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # min verifacation 
+        tdSql.error("select min(ts) from test")
+        tdSql.error("select min(ts) from test1")
+        tdSql.error("select min(col7) from test")
+        tdSql.error("select min(col7) from test1")
+        tdSql.error("select min(col8) from test")
+        tdSql.error("select min(col8) from test1")
+        tdSql.error("select min(col9) from test")
+        tdSql.error("select min(col9) from test1")
+        
+        tdSql.query("select min(col1) from test1")
+        tdSql.checkData(0, 0, np.min(intData))
+
+        tdSql.query("select min(col2) from test1")
+        tdSql.checkData(0, 0, np.min(intData))
+
+        tdSql.query("select min(col3) from test1")
+        tdSql.checkData(0, 0, np.min(intData))
+
+        tdSql.query("select min(col4) from test1")
+        tdSql.checkData(0, 0, np.min(intData))
+        
+        tdSql.query("select min(col5) from test1")
+        tdSql.checkData(0, 0, np.min(floatData))
+
+        tdSql.query("select min(col6) from test1")
+        tdSql.checkData(0, 0, np.min(floatData))
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_operations.py b/tests/pytest/functions/function_operations.py
new file mode 100644
index 0000000000000000000000000000000000000000..ec8da92c95f925f4899826cfd2df05e1f1d9305d
--- /dev/null
+++ b/tests/pytest/functions/function_operations.py
@@ -0,0 +1,86 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # min verifacation 
+        tdSql.error("select ts + col1 from test")
+        tdSql.error("select ts + col1 from test1")
+        tdSql.error("select col1 + col7 from test")
+        tdSql.error("select col1 + col7 from test1")
+        tdSql.error("select col1 + col8 from test")
+        tdSql.error("select col1 + col8 from test1")
+        tdSql.error("select col1 + col9 from test")
+        tdSql.error("select col1 + col9 from test1")
+
+        tdSql.query("select col1 + col2 from test1")
+        tdSql.checkRows(10)
+        tdSql.checkData(0, 0, 2.0)
+        
+        tdSql.query("select col1 + col2 * col3 from test1")
+        tdSql.checkRows(10)
+        tdSql.checkData(1, 0, 6.0)
+
+        tdSql.query("select col1 + col2 * col3 + col3 / col4 + col5 + col6 from test1")
+        tdSql.checkRows(10)
+        tdSql.checkData(0, 0, 3.2)
+
+        tdSql.execute("insert into test1(ts, col1) values(%d, 11)" % (self.ts + 11))
+        tdSql.query("select col1 + col2 from test1")
+        tdSql.checkRows(11)
+        tdSql.checkData(10, 0, None)
+        
+        tdSql.query("select col1 + col2 * col3 from test1")
+        tdSql.checkRows(11)
+        tdSql.checkData(10, 0, None)
+
+        tdSql.query("select col1 + col2 * col3 + col3 / col4 + col5 + col6 from test1")
+        tdSql.checkRows(11)
+        tdSql.checkData(10, 0, None)
+
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_percentile.py b/tests/pytest/functions/function_percentile.py
new file mode 100644
index 0000000000000000000000000000000000000000..aaeb94372e44282da0d83849c18e40857463b42c
--- /dev/null
+++ b/tests/pytest/functions/function_percentile.py
@@ -0,0 +1,140 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20))''')
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # percentile verifacation 
+        tdSql.error("select percentile(ts 20) from test")
+        tdSql.error("select apercentile(ts 20) from test")
+        tdSql.error("select percentile(col7 20) from test")
+        tdSql.error("select apercentile(col7 20) from test")
+        tdSql.error("select percentile(col8 20) from test")        
+        tdSql.error("select apercentile(col8 20) from test")
+        tdSql.error("select percentile(col9 20) from test")
+        tdSql.error("select apercentile(col9 20) from test")        
+
+        tdSql.query("select percentile(col1, 0) from test")        
+        tdSql.checkData(0, 0, np.percentile(intData, 0))
+        tdSql.query("select apercentile(col1, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col1, 50) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 50))
+        tdSql.query("select apercentile(col1, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col1, 100) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 100))
+        tdSql.query("select apercentile(col1, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))  
+
+        tdSql.query("select percentile(col2, 0) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 0))
+        tdSql.query("select apercentile(col2, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col2, 50) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 50))
+        tdSql.query("select apercentile(col2, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col2, 100) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 100)) 
+        tdSql.query("select apercentile(col2, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+
+        tdSql.query("select percentile(col3, 0) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 0))
+        tdSql.query("select apercentile(col3, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col3, 50) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 50))
+        tdSql.query("select apercentile(col3, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col3, 100) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 100))
+        tdSql.query("select apercentile(col3, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+
+        tdSql.query("select percentile(col4, 0) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 0))
+        tdSql.query("select apercentile(col4, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col4, 50) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 50))
+        tdSql.query("select apercentile(col4, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col4, 100) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 100)) 
+        tdSql.query("select apercentile(col4, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+
+        tdSql.query("select percentile(col5, 0) from test")        
+        print("query result: %s" % tdSql.getData(0, 0))
+        print("array result: %s" % np.percentile(floatData, 0))
+        tdSql.query("select apercentile(col5, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col5, 50) from test")
+        print("query result: %s" % tdSql.getData(0, 0))
+        print("array result: %s" % np.percentile(floatData, 50))
+        tdSql.query("select apercentile(col5, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))        
+        tdSql.query("select percentile(col5, 100) from test")
+        print("query result: %s" % tdSql.getData(0, 0))
+        print("array result: %s" % np.percentile(floatData, 100)) 
+        tdSql.query("select apercentile(col5, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))     
+
+        tdSql.query("select percentile(col6, 0) from test")
+        tdSql.checkData(0, 0, np.percentile(floatData, 0))
+        tdSql.query("select apercentile(col6, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col6, 50) from test")
+        tdSql.checkData(0, 0, np.percentile(floatData, 50))
+        tdSql.query("select apercentile(col6, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col6, 100) from test")
+        tdSql.checkData(0, 0, np.percentile(floatData, 100)) 
+        tdSql.query("select apercentile(col6, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))       
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_spread.py b/tests/pytest/functions/function_spread.py
new file mode 100644
index 0000000000000000000000000000000000000000..62b604a279caf5ed9826c32f05e4caf0bb235fa9
--- /dev/null
+++ b/tests/pytest/functions/function_spread.py
@@ -0,0 +1,111 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        tdSql.execute("insert into test1 values(%d, 0, 0, 0, 0, 0.0, 0.0, False, ' ', ' ')" % (self.ts - 1))
+        
+        # spread verifacation 
+        tdSql.query("select spread(ts) from test1")
+        tdSql.checkRows(1)       
+
+        tdSql.query("select spread(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        tdSql.query("select spread(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        tdSql.query("select spread(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        tdSql.query("select spread(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        tdSql.query("select spread(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        tdSql.query("select spread(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+       
+        tdSql.error("select spread(col7) from test")     
+        tdSql.error("select spread(col7) from test1")               
+        tdSql.error("select spread(col8) from test") 
+        tdSql.error("select spread(col8) from test1")
+        tdSql.error("select spread(col9) from test")        
+        tdSql.error("select spread(col9) from test1")
+        
+        tdSql.query("select spread(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select spread(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select spread(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select spread(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select spread(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+
+        tdSql.query("select spread(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_stddev.py b/tests/pytest/functions/function_stddev.py
new file mode 100644
index 0000000000000000000000000000000000000000..23df415aa35feecf84ba40a50604d2b86fc7f008
--- /dev/null
+++ b/tests/pytest/functions/function_stddev.py
@@ -0,0 +1,80 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # stddev verifacation 
+        tdSql.error("select stddev(ts) from test1")
+        tdSql.error("select stddev(col1) from test")
+        tdSql.error("select stddev(col2) from test")
+        tdSql.error("select stddev(col3) from test")
+        tdSql.error("select stddev(col4) from test")
+        tdSql.error("select stddev(col5) from test")
+        tdSql.error("select stddev(col6) from test")
+        tdSql.error("select stddev(col7) from test1")
+        tdSql.error("select stddev(col8) from test1")
+        tdSql.error("select stddev(col9) from test1")
+
+        tdSql.query("select stddev(col1) from test1")
+        tdSql.checkData(0, 0, np.std(intData))
+
+        tdSql.query("select stddev(col2) from test1")
+        tdSql.checkData(0, 0, np.std(intData))
+
+        tdSql.query("select stddev(col3) from test1")
+        tdSql.checkData(0, 0, np.std(intData))
+
+        tdSql.query("select stddev(col4) from test1")
+        tdSql.checkData(0, 0, np.std(intData))
+
+        tdSql.query("select stddev(col5) from test1")
+        tdSql.checkData(0, 0, np.std(floatData))
+
+        tdSql.query("select stddev(col6) from test1")
+        tdSql.checkData(0, 0, np.std(floatData))
+            
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_sum.py b/tests/pytest/functions/function_sum.py
new file mode 100644
index 0000000000000000000000000000000000000000..8e4e289c7ebda5d814d0b64720c17474274f8864
--- /dev/null
+++ b/tests/pytest/functions/function_sum.py
@@ -0,0 +1,70 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # sum verifacation 
+        tdSql.error("select sum(ts) from test")
+        tdSql.error("select sum(col7) from test")
+        tdSql.error("select sum(col8) from test")
+        tdSql.error("select sum(col9) from test")
+
+        tdSql.query("select sum(col1) from test")
+        tdSql.checkData(0, 0, np.sum(intData))
+        tdSql.query("select sum(col2) from test")
+        tdSql.checkData(0, 0, np.sum(intData))
+        tdSql.query("select sum(col3) from test")
+        tdSql.checkData(0, 0, np.sum(intData))
+        tdSql.query("select sum(col4) from test")
+        tdSql.checkData(0, 0, np.sum(intData))
+        tdSql.query("select sum(col5) from test")
+        print("query result for folat sum function: %f" % tdSql.getData(0, 0))
+        print("calculation result for numpy sum function: %f" % np.sum(floatData))
+        tdSql.query("select sum(col6) from test")
+        tdSql.checkData(0, 0, np.sum(floatData))              
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_top.py b/tests/pytest/functions/function_top.py
new file mode 100644
index 0000000000000000000000000000000000000000..e24ff1cc5339c79e1a87653e9b528ec34f3c2ea9
--- /dev/null
+++ b/tests/pytest/functions/function_top.py
@@ -0,0 +1,98 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # top verifacation 
+        tdSql.error("select top(ts, 10) from test")
+        tdSql.error("select top(col1, 0) from test")
+        tdSql.error("select top(col1, 101) from test")
+        tdSql.error("select top(col2, 0) from test")
+        tdSql.error("select top(col2, 101) from test")
+        tdSql.error("select top(col3, 0) from test")
+        tdSql.error("select top(col3, 101) from test")
+        tdSql.error("select top(col4, 0) from test")
+        tdSql.error("select top(col4, 101) from test")
+        tdSql.error("select top(col5, 0) from test")
+        tdSql.error("select top(col5, 101) from test")
+        tdSql.error("select top(col6, 0) from test")
+        tdSql.error("select top(col6, 101) from test")        
+        tdSql.error("select top(col7, 10) from test")        
+        tdSql.error("select top(col8, 10) from test")
+        tdSql.error("select top(col9, 10) from test")
+
+        tdSql.query("select top(col1, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 9)
+        tdSql.checkData(1, 1, 10)
+
+        tdSql.query("select top(col2, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 9)
+        tdSql.checkData(1, 1, 10)
+
+        tdSql.query("select top(col3, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 9)
+        tdSql.checkData(1, 1, 10)
+
+        tdSql.query("select top(col4, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 9)
+        tdSql.checkData(1, 1, 10)
+
+        tdSql.query("select top(col5, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 8.1)
+        tdSql.checkData(1, 1, 9.1)
+
+        tdSql.query("select top(col6, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 8.1)
+        tdSql.checkData(1, 1, 9.1)
+                   
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_twa.py b/tests/pytest/functions/function_twa.py
new file mode 100644
index 0000000000000000000000000000000000000000..1ce4c99b6041e2cfd6bccdbc0e00e5fd8037f9d9
--- /dev/null
+++ b/tests/pytest/functions/function_twa.py
@@ -0,0 +1,135 @@
+###################################################################
+#           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 numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # twa verifacation 
+        tdSql.error("select twa(ts) from test")
+        tdSql.error("select twa(ts) from test1")
+
+        tdSql.error("select twa(col1) from test")
+        tdSql.error("select twa(col1) from test1")
+
+        tdSql.error("select twa(col2) from test")
+        tdSql.error("select twa(col2) from test1")
+
+        tdSql.error("select twa(col3) from test")
+        tdSql.error("select twa(col3) from test1")
+
+        tdSql.error("select twa(col4) from test")
+        tdSql.error("select twa(col4) from test1")
+
+        tdSql.error("select twa(col5) from test")
+        tdSql.error("select twa(col5) from test1")
+
+        tdSql.error("select twa(col6) from test")
+        tdSql.error("select twa(col6) from test1")        
+
+        tdSql.error("select twa(col7) from test")
+        tdSql.error("select twa(col7) from test1")
+
+        tdSql.error("select twa(col8) from test")
+        tdSql.error("select twa(col8) from test1")
+
+        tdSql.error("select twa(col9) from test")
+        tdSql.error("select twa(col9) from test1")
+
+        tdSql.error("select twa(col1) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col1) from test1 where ts > %d" % self.ts)
+
+        tdSql.error("select twa(col2) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col2) from test1 where ts > %d" % self.ts)
+
+        tdSql.error("select twa(col3) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col3) from test1 where ts > %d" % self.ts)
+
+        tdSql.error("select twa(col4) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col4) from test1 where ts > %d" % self.ts)
+            
+        tdSql.error("select twa(col5) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col5) from test1 where ts > %d" % self.ts)
+
+        tdSql.error("select twa(col6) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col6) from test1 where ts > %d" % self.ts)
+
+        tdSql.error("select twa(col1) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col1) from test1 where ts < %d" % (self.ts + self.rowNum))
+
+        tdSql.error("select twa(col2) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col2) from test1 where ts < %d" % (self.ts + self.rowNum))
+
+        tdSql.error("select twa(col3) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col3) from test1 where ts < %d" % (self.ts + self.rowNum))
+
+        tdSql.error("select twa(col4) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col4) from test1 where ts < %d" % (self.ts + self.rowNum))
+
+        tdSql.error("select twa(col5) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col5) from test1 where ts < %d" % (self.ts + self.rowNum))
+
+        tdSql.error("select twa(col6) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col6) from test1 where ts < %d" % (self.ts + self.rowNum))
+        
+        tdSql.query("select twa(col1) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+        tdSql.query("select twa(col1) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+        tdSql.query("select twa(col2) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+        tdSql.query("select twa(col2) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+        tdSql.query("select twa(col3) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+        tdSql.query("select twa(col3) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+        tdSql.query("select twa(col4) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum)) 
+        tdSql.query("select twa(col4) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+        tdSql.query("select twa(col5) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum)) 
+        tdSql.query("select twa(col5) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+        tdSql.query("select twa(col6) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))         
+        tdSql.query("select twa(col6) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/query/filterOtherTypes.py b/tests/pytest/query/filterOtherTypes.py
index 1db5497604923cecd8111015dd0ba497b914b453..5033ffdb48237e6a758d67162af5757cce04252d 100644
--- a/tests/pytest/query/filterOtherTypes.py
+++ b/tests/pytest/query/filterOtherTypes.py
@@ -231,10 +231,12 @@ class TDTestCase:
         tdSql.error("select * from st where tagcol1 like '____'")
 
         # > for nchar type on tag
-        tdSql.error("select * from st where tagcol2 > 'table'")
+        tdSql.query("select * from st where tagcol2 > 'table1'")
+        tdSql.checkRows(5)
 
         # >= for nchar type on tag
-        tdSql.error("select * from st where tagcol2 >= 'table'")
+        tdSql.query("select * from st where tagcol2 >= 'table1'")
+        tdSql.checkRows(10)
 
         # = for nchar type on tag
         tdSql.query("select * from st where tagcol2 = 'table1'")
@@ -249,10 +251,12 @@ class TDTestCase:
         tdSql.checkRows(10)
 
         # > for nchar type on tag
-        tdSql.error("select * from st where tagcol2 < 'table'")
+        tdSql.query("select * from st where tagcol2 < 'table'")
+        tdSql.checkRows(0)
 
         # >= for nchar type on tag
-        tdSql.error("select * from st where tagcol2 <= 'table'")
+        tdSql.query("select * from st where tagcol2 <= 'table'")
+        tdSql.checkRows(0)
 
         # % for nchar type on tag case 1
         tdSql.query("select * from st where tagcol2 like '%'")
@@ -291,10 +295,12 @@ class TDTestCase:
         tdSql.checkRows(10)
 
         # > for binary type on tag
-        tdSql.error("select * from st where tagcol3 > '表'")
+        tdSql.query("select * from st where tagcol3 > '表'")
+        tdSql.checkRows(10)
 
         # >= for binary type on tag
-        tdSql.error("select * from st where tagcol3 >= '表'")
+        tdSql.query("select * from st where tagcol3 >= '表'")
+        tdSql.checkRows(10)
 
         # = for binary type on tag
         tdSql.query("select * from st where tagcol3 = '水表'")
@@ -309,10 +315,12 @@ class TDTestCase:
         tdSql.checkRows(5)
 
         # > for binary type on tag
-        tdSql.error("select * from st where tagcol3 < '水表'")
+        tdSql.query("select * from st where tagcol3 < '水表'")
+        tdSql.checkRows(0)
 
         # >= for binary type on tag
-        tdSql.error("select * from st where tagcol3 <= '水表'")
+        tdSql.query("select * from st where tagcol3 <= '水表'")
+        tdSql.checkRows(5)
 
         # % for binary type on tag case 1
         tdSql.query("select * from st where tagcol3 like '%'")
diff --git a/tests/pytest/regressiontest.sh b/tests/pytest/regressiontest.sh
index 24cd93f0fc58772e2d1741d9ee0119d9d5247357..61ec491f5de6ed946aafe3e0f549c233f6a250b7 100755
--- a/tests/pytest/regressiontest.sh
+++ b/tests/pytest/regressiontest.sh
@@ -141,6 +141,7 @@ python3 ./test.py -f query/filterCombo.py
 python3 ./test.py -f query/queryNormal.py
 python3 ./test.py -f query/select_last_crash.py
 python3 ./test.py -f query/queryNullValueTest.py
+python3 ./test.py -f query/queryInsertValue.py
 
 #stream
 python3 ./test.py -f stream/stream1.py
@@ -155,3 +156,23 @@ python3 ./test.py -f client/client.py
 # Misc
 python3 testCompress.py
 python3 testNoCompress.py
+
+
+# functions
+python3 ./test.py -f functions/function_avg.py
+python3 ./test.py -f functions/function_bottom.py
+python3 ./test.py -f functions/function_count.py
+python3 ./test.py -f functions/function_diff.py
+python3 ./test.py -f functions/function_first.py
+python3 ./test.py -f functions/function_last.py
+python3 ./test.py -f functions/function_last_row.py
+python3 ./test.py -f functions/function_leastsquares.py
+python3 ./test.py -f functions/function_max.py
+python3 ./test.py -f functions/function_min.py
+python3 ./test.py -f functions/function_operations.py
+python3 ./test.py -f functions/function_percentile.py
+python3 ./test.py -f functions/function_spread.py
+python3 ./test.py -f functions/function_stddev.py
+python3 ./test.py -f functions/function_sum.py
+python3 ./test.py -f functions/function_top.py
+python3 ./test.py -f functions/function_twa.py
diff --git a/tests/pytest/util/sql.py b/tests/pytest/util/sql.py
index ec39ab61b9be2a52031dfcbb786cd6bc88fef555..1e1d02959f58e716a534a164aa72e3d18176d7c0 100644
--- a/tests/pytest/util/sql.py
+++ b/tests/pytest/util/sql.py
@@ -122,11 +122,16 @@ class TDSql:
         return self.cursor.istype(col, dataType)
 
     def checkData(self, row, col, data):
-        self.checkRowCol(row, col)
-        if self.queryResult[row][col] != data:
-            caller = inspect.getframeinfo(inspect.stack()[1][0])
-            args = (caller.filename, caller.lineno, self.sql, row, col, self.queryResult[row][col], data)
-            tdLog.exit("%s(%d) failed: sql:%s row:%d col:%d data:%s != expect:%s" % args)
+        self.checkRowCol(row, col)                
+        if self.queryResult[row][col] != 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)) 
+                return
+            else:
+                caller = inspect.getframeinfo(inspect.stack()[1][0])
+                args = (caller.filename, caller.lineno, self.sql, row, col, self.queryResult[row][col], data)
+                tdLog.exit("%s(%d) failed: sql:%s row:%d col:%d data:%s != expect:%s" % args)        
 
         if data is None:
             tdLog.info("sql:%s, row:%d col:%d data:%s == expect:%s" %
@@ -135,9 +140,12 @@ class TDSql:
             tdLog.info("sql:%s, row:%d col:%d data:%s == expect:%s" %
                        (self.sql, row, col, self.queryResult[row][col], data))
         elif isinstance(data, datetime.date):
+            tdLog.info("sql:%s, row:%d col:%d data:%s == expect:%s" %
+                       (self.sql, row, col, self.queryResult[row][col], data))        
+        elif isinstance(data, float):
             tdLog.info("sql:%s, row:%d col:%d data:%s == expect:%s" %
                        (self.sql, row, col, self.queryResult[row][col], data))
-        else:
+        else:            
             tdLog.info("sql:%s, row:%d col:%d data:%s == expect:%d" %
                        (self.sql, row, col, self.queryResult[row][col], data))