diff --git a/tests/system-test/2-query/Now.py b/tests/system-test/2-query/Now.py
index 99fca2e88d4bc10591861a800580312ae7689ab5..9d073eb4f73ff8facad147b3c2e90ac8e6eabe30 100644
--- a/tests/system-test/2-query/Now.py
+++ b/tests/system-test/2-query/Now.py
@@ -144,6 +144,12 @@ class TDTestCase:
 
         tdSql.error("select now()+1.5 from ntb")
         tdSql.error("select now()+1.5 from db.ntb")
+        tdSql.error("select now()-1.5 from ntb")
+        tdSql.error("select now()-1.5 from db.ntb")
+        tdSql.error("select now()*1.5 from ntb")
+        tdSql.error("select now()*1.5 from db.ntb")
+        tdSql.error("select now()/1.5 from ntb")
+        tdSql.error("select now()/1.5 from db.ntb")
         tdSql.error("select now()+'abc' from ntb")
         tdSql.error("select now()+'abc' from db.ntb")
         tdSql.error("select now()+abc from ntb")
@@ -262,7 +268,10 @@ class TDTestCase:
         tdSql.checkRows(3)
         tdSql.query("select now() +1 from db.stb")
         tdSql.checkRows(3)
-
+        tdSql.error("select now() +1.5 from stb")
+        tdSql.error("select now() -1.5 from stb")
+        tdSql.error("select now() *1.5 from stb")
+        tdSql.error("select now() /1.5 from stb")
         tdSql.error("select now() +'abc' from stb")
         tdSql.error("select now() +'abc' from db.stb")
         tdSql.error("select now() + ! from stb")
@@ -272,6 +281,7 @@ class TDTestCase:
         tdSql.error("select now() -today() from stb")
         tdSql.error("select now() - today() from db.stb")
 
+
         tdSql.query("select now()+null from stb")
         tdSql.checkData(0,0,None)
         tdSql.query("select now()+null from db.stb")
diff --git a/tests/system-test/2-query/Timediff.py b/tests/system-test/2-query/Timediff.py
new file mode 100644
index 0000000000000000000000000000000000000000..2824fea5a291f9426b9460fb66d174a5418d1d61
--- /dev/null
+++ b/tests/system-test/2-query/Timediff.py
@@ -0,0 +1,196 @@
+from util.log import *
+from util.sql import *
+from util.cases import *
+
+class TDTestCase:
+    
+    def init(self, conn, logSql):
+        tdLog.debug(f"start to excute {__file__}")
+        tdSql.init(conn.cursor())
+
+    def run(self):  # sourcery skip: extract-duplicate-method
+        tdSql.prepare()
+        tdLog.printNoPrefix("==========step1:create tables==========")
+        tdSql.execute(
+            '''create table if not exists ntb
+            (ts timestamp, c1 int, c2 float,c3 double,c4 timestamp)
+            '''
+        )
+        tdSql.execute(
+            '''create table if not exists stb
+            (ts timestamp, c1 int, c2 float,c3 double,c4 timestamp) tags(t0 int)
+            '''
+        )
+        tdSql.execute(
+            '''create table if not exists stb_1 using stb tags(100)
+            '''
+        )
+        tdLog.printNoPrefix("==========step2:insert data into ntb==========")
+
+        # RFC3339:2020-01-01T00:00:00+8:00
+        # ISO8601:2020-01-01T00:00:00.000+0800
+        tdSql.execute(
+            'insert into ntb values(now,1,1.55,100.555555,today())("2020-1-1 00:00:00",10,11.11,99.999999,now())(today(),3,3.333,333.333333,now())')
+        tdSql.execute(
+            'insert into stb_1 values(now,1,1.55,100.555555,today())("2020-1-1 00:00:00",10,11.11,99.999999,now())(today(),3,3.333,333.333333,now())')
+        
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00') from ntb")
+        tdSql.checkRows(3)
+        tdSql.query("select timediff(1,0,1d) from ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff(1,0,1d) from db.ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff(1,0,1s) from ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,1)
+        tdSql.query("select timediff(1,0,1s) from db.ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,1)
+        tdSql.query("select timediff(1,0,1w) from ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff(1,0,1w) from db.ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff(1,0,1h) from ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff(1,0,1h) from db.ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff(1,0,1m) from ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff(1,0,1m) from db.ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff(1,0,1a) from ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,1000)
+        tdSql.query("select timediff(1,0,1a) from db.ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,1000)
+        tdSql.query("select timediff(1,0,1u) from ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,1000000)
+        tdSql.query("select timediff(1,0,1u) from db.ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,1000000)
+
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00') from stb")
+        tdSql.checkRows(3)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00') from db.stb")
+        tdSql.checkRows(3)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1d) from stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,1)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1d) from db.stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,1)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1h) from stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,24)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1h) from db.stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,24)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1w) from stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1m) from stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,1440)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1m) from db.stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,1440)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1s) from stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,86400)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1s) from db.stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,86400)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1a) from stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,86400000)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1a) from db.stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,86400000)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1u) from stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,86400000000)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-2 00:00:00',1u) from db.stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,86400000000)
+
+
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00') from stb_1")
+        tdSql.checkRows(3)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00') from db.stb_1")
+        tdSql.checkRows(3)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1w) from stb_1 ")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1w) from db.stb_1 ")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1d) from stb_1 ")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1d) from db.stb_1 ")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,0)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1h) from stb_1 ")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,12)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1h) from db.stb_1 ")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,12)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1m) from stb_1" )
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,720)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1m) from db.stb_1" )
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,720)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1s) from stb_1")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,43200)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1s) from db.stb_1")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,43200)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1a) from stb_1")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,43200000)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1a) from db.stb_1")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,43200000)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1u) from stb_1")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,43200000000)
+        tdSql.query("select timediff('2020-1-1 00:00:00','2020-1-1 12:00:00',1u) from db.stb_1")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,43200000000)
+
+        tdSql.query("select timediff('a','b') from stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,None)
+        tdSql.checkData(1,0,None)
+        tdSql.checkData(2,0,None)
+        tdSql.error("select timediff(1.5,1.5) from stb")
+        tdSql.error("select timediff(1) from stb")
+        tdSql.error("select timediff(10,1,1.5) from stb")
+        # tdSql.error("select timediff(10,1,2s) from stb")
+        # tdSql.error("select timedifff(10,1,c1) from stb")
+
+
+
+
+
+
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success(f"{__file__} successfully executed")
+
+tdCases.addLinux(__file__, TDTestCase())
+tdCases.addWindows(__file__, TDTestCase())
\ No newline at end of file
diff --git a/tests/system-test/2-query/To_iso8061.py b/tests/system-test/2-query/To_iso8601.py
similarity index 88%
rename from tests/system-test/2-query/To_iso8061.py
rename to tests/system-test/2-query/To_iso8601.py
index 86322ed0763c23a8e350088a0e7027cc67c779df..cd22ffb90c1fbf86e81dfabecbcb1ae0e536cd39 100644
--- a/tests/system-test/2-query/To_iso8061.py
+++ b/tests/system-test/2-query/To_iso8601.py
@@ -92,6 +92,21 @@ class TDTestCase:
         tdSql.query("select to_iso8601(today()) /null from db.ntb")
         tdSql.checkRows(3)
         tdSql.checkData(0,0,None)
+        # tdSql.query("select to_iso8601(-1) from ntb")
+        tdSql.query("select to_iso8601(9223372036854775807) from ntb")
+        tdSql.checkRows(3)
+
+        # tdSql.query("select to_iso8601(10000000000) from ntb")
+        # tdSql.checkData(0,0,None)
+        # tdSql.query("select to_iso8601(-1) from ntb")
+        # tdSql.checkRows(3)
+        # tdSql.query("select to_iso8601(-10000000000) from ntb")
+        # tdSql.checkData(0,0,None)
+        tdSql.error("select to_iso8601(1.5) from ntb")
+        tdSql.error("select to_iso8601(1.5) from db.ntb")
+        tdSql.error("select to_iso8601('a') from ntb")
+        tdSql.error("select to_iso8601(c2) from ntb")
+        
 
 
 
@@ -137,6 +152,8 @@ class TDTestCase:
         tdSql.checkRows(3)
         tdSql.checkData(0,0,None)
 
+        # tdSql.query("select to_iso8601(-1) from ntb")
+
 
 
     def stop(self):
diff --git a/tests/system-test/2-query/To_unixtimestamp.py b/tests/system-test/2-query/To_unixtimestamp.py
new file mode 100644
index 0000000000000000000000000000000000000000..43315ff0d893dc5c5e2a118dd652980aad1fedb5
--- /dev/null
+++ b/tests/system-test/2-query/To_unixtimestamp.py
@@ -0,0 +1,73 @@
+from time import sleep
+
+from util.log import *
+from util.sql import *
+from util.cases import *
+
+
+
+
+class TDTestCase:
+
+    def init(self, conn, logSql):
+        tdLog.debug(f"start to excute {__file__}")
+        tdSql.init(conn.cursor())
+
+    def run(self):  # sourcery skip: extract-duplicate-method
+        tdSql.prepare()
+        tdLog.printNoPrefix("==========step1:create tables==========")
+        tdSql.execute(
+            '''create table if not exists ntb
+            (ts timestamp, c1 int, c2 float,c3 double,c4 timestamp)
+            '''
+        )
+        tdSql.execute(
+            '''create table if not exists stb
+            (ts timestamp, c1 int, c2 float,c3 double,c4 timestamp) tags(t0 int)
+            '''
+        )
+        tdSql.execute(
+            '''create table if not exists stb_1 using stb tags(100)
+            '''
+        )
+        tdLog.printNoPrefix("==========step2:insert data into ntb==========")
+
+        # RFC3339:2020-01-01T00:00:00+8:00
+        # ISO8601:2020-01-01T00:00:00.000+0800
+        tdSql.execute(
+            'insert into ntb values(now,1,1.55,100.555555,today())("2020-1-1 00:00:00",10,11.11,99.999999,now())(today(),3,3.333,333.333333,now())')
+        tdSql.execute(
+            'insert into stb_1 values(now,1,1.55,100.555555,today())("2020-1-1 00:00:00",10,11.11,99.999999,now())(today(),3,3.333,333.333333,now())')
+        tdSql.query("select to_unixtimestamp('1970-01-01T08:00:00+0800') from ntb")
+        tdSql.checkData(0,0,0)
+        tdSql.checkData(1,0,0)
+        tdSql.checkData(2,0,0)
+        tdSql.checkRows(3)
+        tdSql.query("select to_unixtimestamp('1970-01-01T08:00:00+08:00') from ntb")
+        tdSql.checkData(0,0,0)
+        tdSql.checkRows(3)
+        tdSql.query("select to_unixtimestamp('1900-01-01T08:00:00+08:00') from ntb")
+        tdSql.checkRows(3)
+        tdSql.query("select to_unixtimestamp('2020-01-32T08:00:00') from ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,None)
+        tdSql.query("select to_unixtimestamp('2020-13-32T08:00:00') from ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,None)
+        tdSql.query("select to_unixtimestamp('acd') from ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,None)
+        tdSql.error("select to_unixtimestamp(1) from ntb")
+        tdSql.error("select to_unixtimestamp(1.5) from ntb")
+        tdSql.error("select to_unixtimestamp(ts) from ntb")
+
+        tdSql.query("select ts from ntb where to_unixtimestamp('1970-01-01T08:00:00+08:00')=0")
+        tdSql.checkRows(3)
+        
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success(f"{__file__} successfully executed")
+
+tdCases.addLinux(__file__, TDTestCase())
+tdCases.addWindows(__file__, TDTestCase())
\ No newline at end of file
diff --git a/tests/system-test/2-query/Today.py b/tests/system-test/2-query/Today.py
index 09f018dc11d6a9aae35b484d4649a36f2321e4b8..9eb06de9fb16731bbaa69460f24f4ecff78a2ff3 100644
--- a/tests/system-test/2-query/Today.py
+++ b/tests/system-test/2-query/Today.py
@@ -134,6 +134,35 @@ class TDTestCase:
         tdSql.checkRows(3)
         tdSql.checkData(0, 0, str(today_date))
 
+        tdSql.error("select today()+1.5 from ntb")
+        tdSql.error("select today()-1.5 from ntb")
+        tdSql.error("select today()*1.5 from ntb")
+        tdSql.error("select today()/1.5 from ntb")
+        tdSql.error("select today()+1.5 from db.ntb")
+        tdSql.error("select today()-1.5 from db.ntb")
+        tdSql.error("select today()*1.5 from db.ntb")
+        tdSql.error("select today()/1.5 from db.ntb")
+        tdSql.query("select today()+null from ntb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()+null from db.ntb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()-null from ntb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()-null from db.ntb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()*null from ntb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()*null from db.ntb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()/null from ntb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()/null from db.ntb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()/0 from db.ntb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,None)
+        tdSql.checkData(1,0,None)
+        tdSql.checkData(2,0,None)
         # stable
         tdSql.query("select today() from stb")
         tdSql.checkRows(3)
@@ -208,6 +237,26 @@ class TDTestCase:
         tdSql.query("select ts from stb where ts<=today()")
         tdSql.checkRows(2)
 
+        tdSql.error("select today()+1.5 from stb")
+        tdSql.error("select today()-1.5 from stb")
+        tdSql.error("select today()*1.5 from stb")
+        tdSql.error("select today()/1.5 from stb")
+        tdSql.query("select today()+null from stb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()+null from db.stb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()-null from stb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()-null from db.stb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()*null from stb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()*null from db.stb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()/null from stb")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()/null from db.stb")
+        tdSql.checkData(0,0,None)
         # 
         # tdSql.query("select * from ntb where ts<today()")
         # tdSql.checkRows(1)
@@ -220,6 +269,11 @@ class TDTestCase:
         tdSql.checkData(0, 0, str(today_date))
         tdSql.query("select today() from stb where ts<now()")
         tdSql.checkRows(3)
+        tdSql.query("select today()/0 from db.stb")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,None)
+        tdSql.checkData(1,0,None)
+        tdSql.checkData(2,0,None)
 
         # table
         tdSql.query("select today() from stb_1")
@@ -309,7 +363,31 @@ class TDTestCase:
         tdSql.checkRows(1)
         tdSql.query("select today() from stb_1 where ts<now()")
         tdSql.checkRows(3)
-
+        tdSql.error("select today()+1.5 from stb_1")
+        tdSql.error("select today()-1.5 from stb_1")
+        tdSql.error("select today()*1.5 from stb_1")
+        tdSql.error("select today()/1.5 from stb_1")
+        tdSql.query("select today()+null from stb_1")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()+null from db.stb_1")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()-null from stb_1")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()-null from db.stb_1")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()*null from stb_1")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()*null from db.stb_1")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()/null from stb_1")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()/null from db.stb_1")
+        tdSql.checkData(0,0,None)
+        tdSql.query("select today()/0 from db.stb_1")
+        tdSql.checkRows(3)
+        tdSql.checkData(0,0,None)
+        tdSql.checkData(1,0,None)
+        tdSql.checkData(2,0,None)
     def stop(self):
         tdSql.close()
         tdLog.success(f"{__file__} successfully executed")
diff --git a/tests/system-test/2-query/count.py b/tests/system-test/2-query/count.py
new file mode 100644
index 0000000000000000000000000000000000000000..a70a2e72f25380d45d799d49ca240b2eb59e52a3
--- /dev/null
+++ b/tests/system-test/2-query/count.py
@@ -0,0 +1,196 @@
+from util.log import *
+from util.sql import *
+from util.cases import *
+
+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()
+
+        tdSql.execute('''create table stb(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20), col11 tinyint unsigned, col12 smallint unsigned, col13 int unsigned, col14 bigint unsigned) tags(loc nchar(20))''')
+        tdSql.execute("create table stb_1 using stb tags('beijing')")
+        tdSql.execute("create table stb_2 using stb tags('shanghai')")
+
+        tdSql.execute('''create table ntb(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20), col11 tinyint unsigned, col12 smallint unsigned, col13 int unsigned, col14 bigint unsigned)''')
+        
+        for i in range(self.rowNum):
+            tdSql.execute("insert into stb_1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))
+            tdSql.execute("insert into stb_2 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))
+        
+        for i in range(self.rowNum):
+            tdSql.execute("insert into ntb values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))
+        
+        tdSql.query("select count(*) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(*) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(ts) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(ts) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col1) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col1) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col2) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col2) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col3) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col3) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col4) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col4) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col5) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col5) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col6) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col6) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col7) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col7) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col8) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col8) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col9) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col9) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col11) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col11) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col12) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col12) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col13) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col13) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col14) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col14) from db.stb")
+        tdSql.checkData(0,0,20)
+
+
+
+        tdSql.query("select count(ts) from db.stb_1")
+        tdSql.checkData(0,0,10)        
+        tdSql.query("select count(ts) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col1) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col1) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col2) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col2) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col3) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col3) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col4) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col4) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col5) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col5) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col6) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col6) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col7) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col7) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col8) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col8) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col9) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col9) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col11) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col11) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col12) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col12) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col13) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col13) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col14) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col14) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col1) from stb_1 group by col7")
+        tdSql.checkRows(2)
+
+        tdSql.execute("insert into stb_1 values(now,null,null,null,null,null,null,null,null,null,null,null,null,null)")
+        tdSql.query("select count(col1) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col1),count(ts) from stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.checkData(0,1,11)
+
+        tdSql.query("select count(col1) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.query("select count(col1),count(ts) from db.stb_1")
+        tdSql.checkData(0,0,10)
+        tdSql.checkData(0,1,11)
+
+        tdSql.query("select count(col1) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col1),count(ts) from stb")
+        tdSql.checkData(0,0,20)
+        tdSql.checkData(0,1,21)
+        
+        tdSql.query("select count(col1) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.query("select count(col1),count(ts) from db.stb")
+        tdSql.checkData(0,0,20)
+        tdSql.checkData(0,1,21)
+        tdSql.query("select count(col1) from stb_1 group by col7")
+        tdSql.checkRows(3)
+        tdSql.query("select count(col1) from stb_2 group by col7")
+        tdSql.checkRows(2)
+        tdSql.query("select count(col1) from stb group by col7")
+        tdSql.checkRows(3)
+
+        
+
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file
diff --git a/tests/system-test/2-query/last.py b/tests/system-test/2-query/last.py
new file mode 100644
index 0000000000000000000000000000000000000000..b5c0498e40fa1d17aec48294d98e124a89d3f935
--- /dev/null
+++ b/tests/system-test/2-query/last.py
@@ -0,0 +1,331 @@
+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()
+
+        tdSql.execute('''create table stb(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20), col11 tinyint unsigned, col12 smallint unsigned, col13 int unsigned, col14 bigint unsigned) tags(loc nchar(20))''')
+        tdSql.execute("create table stb_1 using stb tags('beijing')")
+        tdSql.execute("insert into stb_1(ts) values(%d)" % (self.ts - 1))
+
+        # last verifacation         
+        # tdSql.query("select last(*) from stb_1")
+        # tdSql.checkRows(1)
+        # tdSql.checkData(0, 1, None)
+        # tdSql.query("select last(*) from db.stb_1")
+        # tdSql.checkRows(1)
+        # tdSql.checkData(0, 1, None)
+        tdSql.query("select last(col1) from stb_1")
+        tdSql.checkRows(0) 
+        tdSql.query("select last(col1) from db.stb_1")
+        tdSql.checkRows(0)       
+        tdSql.query("select last(col2) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col2) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col3) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col3) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col4) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col4) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col11) from stb_1")
+        tdSql.checkRows(0)    
+        tdSql.query("select last(col11) from db.stb_1")
+        tdSql.checkRows(0)      
+        tdSql.query("select last(col12) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col12) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col13) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col13) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col14) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col14) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col5) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col5) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col6) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col6) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col7) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col7) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col8) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col8) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col9) from stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col9) from db.stb_1")
+        tdSql.checkRows(0)
+        tdSql.query("select count(col1) from stb_1 group by col7")
+        tdSql.checkRows(1)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into stb_1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))            
+
+        # tdSql.query("select last(*) from stb_1")
+        # tdSql.checkRows(1)
+        # tdSql.checkData(0, 1, 10)
+        # tdSql.query("select last(*) from db.stb_1")
+        # tdSql.checkRows(1)
+        # tdSql.checkData(0, 1, 10)
+        tdSql.query("select last(col1) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col1) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col2) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col2) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col3) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col3) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col4) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col4) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col11) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col11) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col12) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col12) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col13) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col13) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col14) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col14) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col5) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+        tdSql.query("select last(col5) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+        tdSql.query("select last(col6) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+        tdSql.query("select last(col6) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+        tdSql.query("select last(col7) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, True)
+        tdSql.query("select last(col7) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, True)
+        tdSql.query("select last(col8) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'taosdata10')
+        tdSql.query("select last(col8) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'taosdata10')
+        tdSql.query("select last(col9) from stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, '涛思数据10')
+        tdSql.query("select last(col9) from db.stb_1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, '涛思数据10')
+
+
+        tdSql.execute('''create table ntb(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20), col11 tinyint unsigned, col12 smallint unsigned, col13 int unsigned, col14 bigint unsigned)''')
+        tdSql.execute("insert into ntb(ts) values(%d)" % (self.ts - 1))
+        # tdSql.query("select last(*) from ntb")
+        # tdSql.checkRows(1)
+        # tdSql.checkData(0, 1, None)
+        # tdSql.query("select last(*) from db.ntb")
+        # tdSql.checkRows(1)
+        # tdSql.checkData(0, 1, None)
+        tdSql.query("select last(col1) from ntb")
+        tdSql.checkRows(0) 
+        tdSql.query("select last(col1) from db.ntb")
+        tdSql.checkRows(0)       
+        tdSql.query("select last(col2) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col2) from db.ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col3) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col3) from db.ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col4) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col4) from db.ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col11) from ntb")
+        tdSql.checkRows(0)    
+        tdSql.query("select last(col11) from db.ntb")
+        tdSql.checkRows(0)      
+        tdSql.query("select last(col12) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col12) from db.ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col13) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col13) from db.ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col14) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col14) from db.ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col5) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col5) from db.ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col6) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col6) from db.ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col7) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col7) from db.ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col8) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col8) from db.ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col9) from ntb")
+        tdSql.checkRows(0)
+        tdSql.query("select last(col9) from db.ntb")
+        tdSql.checkRows(0)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into ntb values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))            
+
+        tdSql.query("select last(*) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, 10)
+        tdSql.query("select last(*) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, 10)
+        tdSql.query("select last(col1) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col1) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col2) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col2) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col3) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col3) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col4) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col4) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col11) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col11) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col12) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col12) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col13) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col13) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col14) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col14) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select last(col5) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+        tdSql.query("select last(col5) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+        tdSql.query("select last(col6) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+        tdSql.query("select last(col6) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+        tdSql.query("select last(col7) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, True)
+        tdSql.query("select last(col7) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, True)
+        tdSql.query("select last(col8) from ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'taosdata10')
+        tdSql.query("select last(col8) from db.ntb")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'taosdata10')
+        # tdSql.query("select last(col9) from ntb")
+        # tdSql.checkRows(1)
+        # tdSql.checkData(0, 0, '涛思数据10')
+        # tdSql.query("select last(col9) from db.ntb")
+        # 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())
\ No newline at end of file
diff --git a/tests/system-test/2-query/max.py b/tests/system-test/2-query/max.py
new file mode 100644
index 0000000000000000000000000000000000000000..5342c7d44988949f4754040b77ea416d20b79658
--- /dev/null
+++ b/tests/system-test/2-query/max.py
@@ -0,0 +1,205 @@
+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 prepare_data(self):
+        
+        pass    
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table stb(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20), col11 tinyint unsigned, col12 smallint unsigned, col13 int unsigned, col14 bigint unsigned) tags(loc nchar(20))''')
+        tdSql.execute("create table stb_1 using stb tags('beijing')")
+        tdSql.execute('''create table ntb(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20), col11 tinyint unsigned, col12 smallint unsigned, col13 int unsigned, col14 bigint unsigned)''')
+        for i in range(self.rowNum):
+            tdSql.execute("insert into ntb values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)
+        for i in range(self.rowNum):
+            tdSql.execute("insert into stb_1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # max verifacation 
+        tdSql.error("select max(ts) from stb_1")
+        tdSql.error("select max(ts) from db.stb_1")
+        tdSql.error("select max(col7) from stb_1")
+        tdSql.error("select max(col7) from db.stb_1")
+        tdSql.error("select max(col8) from stb_1")
+        tdSql.error("select max(col8) from db.stb_1")
+        tdSql.error("select max(col9) from stb_1")
+        tdSql.error("select max(col9) from db.stb_1")
+
+        tdSql.query("select max(col1) from stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col1) from db.stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col2) from stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col2) from db.stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col3) from stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col3) from db.stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col4) from stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col4) from db.stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col11) from stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col11) from db.stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col12) from stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col12) from db.stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col13) from stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col13) from db.stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col14) from stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col14) from db.stb_1")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col5) from stb_1")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col5) from db.stb_1")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col6) from stb_1")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col6) from db.stb_1")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col1) from stb_1 where col2<=5")
+        tdSql.checkData(0,0,5)
+        
+
+
+        tdSql.error("select max(ts) from stb")
+        tdSql.error("select max(ts) from db.stb")
+        tdSql.error("select max(col7) from stb")
+        tdSql.error("select max(col7) from db.stb")
+        tdSql.error("select max(col8) from stb")
+        tdSql.error("select max(col8) from db.stb")
+        tdSql.error("select max(col9) from stb")
+        tdSql.error("select max(col9) from db.stb")
+
+        tdSql.query("select max(col1) from stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col1) from db.stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col2) from stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col2) from db.stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col3) from stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col3) from db.stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col4) from stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col4) from db.stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col11) from stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col11) from db.stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col12) from stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col12) from db.stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col13) from stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col13) from db.stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col14) from stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col14) from db.stb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col5) from stb")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col5) from db.stb")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col6) from stb")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col6) from db.stb")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col1) from stb where col2<=5")
+        tdSql.checkData(0,0,5)
+
+
+
+        tdSql.error("select max(ts) from ntb")
+        tdSql.error("select max(ts) from db.ntb")
+        tdSql.error("select max(col7) from ntb")
+        tdSql.error("select max(col7) from db.ntb")
+        tdSql.error("select max(col8) from ntb")
+        tdSql.error("select max(col8) from db.ntb")
+        tdSql.error("select max(col9) from ntb")
+        tdSql.error("select max(col9) from db.ntb")
+
+        tdSql.query("select max(col1) from ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col1) from db.ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col2) from ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col2) from db.ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col3) from ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col3) from db.ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col4) from ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col4) from db.ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col11) from ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col11) from db.ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col12) from ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col12) from db.ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col13) from ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col13) from db.ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col14) from ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col14) from db.ntb")
+        tdSql.checkData(0, 0, np.max(intData))
+        tdSql.query("select max(col5) from ntb")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col5) from db.ntb")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col6) from ntb")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col6) from db.ntb")
+        tdSql.checkData(0, 0, np.max(floatData))
+        tdSql.query("select max(col1) from stb_1 where col2<=5")
+        tdSql.checkData(0,0,5)
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/system-test/2-query/min.py b/tests/system-test/2-query/min.py
new file mode 100644
index 0000000000000000000000000000000000000000..60a8c105f1520df5b1ad8277e79a7608afe474c8
--- /dev/null
+++ b/tests/system-test/2-query/min.py
@@ -0,0 +1,215 @@
+from wsgiref.headers import tspecials
+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 stb(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20), col11 tinyint unsigned, col12 smallint unsigned, col13 int unsigned, col14 bigint unsigned) tags(loc nchar(20))''')
+        tdSql.execute("create table stb_1 using stb tags('beijing')")
+        tdSql.execute('''create table ntb(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20), col11 tinyint unsigned, col12 smallint unsigned, col13 int unsigned, col14 bigint unsigned)''')
+        for i in range(self.rowNum):
+            tdSql.execute("insert into ntb values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)
+        for i in range(self.rowNum):
+            tdSql.execute("insert into stb_1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # max verifacation 
+        tdSql.error("select min(ts) from stb_1")
+        tdSql.error("select min(ts) from db.stb_1")
+        tdSql.error("select min(col7) from stb_1")
+        tdSql.error("select min(col7) from db.stb_1")
+        tdSql.error("select min(col8) from stb_1")
+        tdSql.error("select min(col8) from db.stb_1")
+        tdSql.error("select min(col9) from stb_1")
+        tdSql.error("select min(col9) from db.stb_1")
+        # tdSql.error("select min(a) from stb_1")
+        # tdSql.error("select min(1) from stb_1")
+        tdSql.error("select min(now()) from stb_1")
+        tdSql.error("select min(count(c1),count(c2)) from stb_1")
+
+        tdSql.query("select min(col1) from stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col1) from db.stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col2) from stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col2) from db.stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col3) from stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col3) from db.stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col4) from stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col4) from db.stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col11) from stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col11) from db.stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col12) from stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col12) from db.stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col13) from stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col13) from db.stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col14) from stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col14) from db.stb_1")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col5) from stb_1")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col5) from db.stb_1")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col6) from stb_1")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col6) from db.stb_1")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col1) from stb_1 where col2>=5")
+        tdSql.checkData(0,0,5)
+
+
+        tdSql.error("select min(ts) from stb_1")
+        tdSql.error("select min(ts) from db.stb_1")
+        tdSql.error("select min(col7) from stb_1")
+        tdSql.error("select min(col7) from db.stb_1")
+        tdSql.error("select min(col8) from stb_1")
+        tdSql.error("select min(col8) from db.stb_1")
+        tdSql.error("select min(col9) from stb_1")
+        tdSql.error("select min(col9) from db.stb_1")
+        # tdSql.error("select min(a) from stb_1")
+        # tdSql.error("select min(1) from stb_1")
+        tdSql.error("select min(now()) from stb_1")
+        tdSql.error("select min(count(c1),count(c2)) from stb_1")
+
+        tdSql.query("select min(col1) from stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col1) from db.stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col2) from stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col2) from db.stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col3) from stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col3) from db.stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col4) from stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col4) from db.stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col11) from stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col11) from db.stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col12) from stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col12) from db.stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col13) from stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col13) from db.stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col14) from stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col14) from db.stb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col5) from stb")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col5) from db.stb")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col6) from stb")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col6) from db.stb")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col1) from stb where col2>=5")
+        tdSql.checkData(0,0,5)
+
+
+        tdSql.error("select min(ts) from ntb")
+        tdSql.error("select min(ts) from db.ntb")
+        tdSql.error("select min(col7) from ntb")
+        tdSql.error("select min(col7) from db.ntb")
+        tdSql.error("select min(col8) from ntb")
+        tdSql.error("select min(col8) from db.ntb")
+        tdSql.error("select min(col9) from ntb")
+        tdSql.error("select min(col9) from db.ntb")
+        # tdSql.error("select min(a) from stb_1")
+        # tdSql.error("select min(1) from stb_1")
+        tdSql.error("select min(now()) from ntb")
+        tdSql.error("select min(count(c1),count(c2)) from ntb")
+
+        tdSql.query("select min(col1) from ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col1) from db.ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col2) from ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col2) from db.ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col3) from ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col3) from db.ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col4) from ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col4) from db.ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col11) from ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col11) from db.ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col12) from ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col12) from db.ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col13) from ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col13) from db.ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col14) from ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col14) from db.ntb")
+        tdSql.checkData(0, 0, np.min(intData))
+        tdSql.query("select min(col5) from ntb")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col5) from db.ntb")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col6) from ntb")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col6) from db.ntb")
+        tdSql.checkData(0, 0, np.min(floatData))
+        tdSql.query("select min(col1) from ntb where col2>=5")
+        tdSql.checkData(0,0,5)
+
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/system-test/2-query/timetruncate.py b/tests/system-test/2-query/timetruncate.py
new file mode 100644
index 0000000000000000000000000000000000000000..a48851b251235b6c6acd84b1b81d82c2cd54c7dd
--- /dev/null
+++ b/tests/system-test/2-query/timetruncate.py
@@ -0,0 +1,220 @@
+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  # 2018-9-17 09:00:00.000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table stb(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20), col11 tinyint unsigned, col12 smallint unsigned, col13 int unsigned, col14 bigint unsigned) tags(loc nchar(20))''')
+        tdSql.execute("create table stb_1 using stb tags('beijing')")
+        tdSql.execute('''create table ntb(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20), col11 tinyint unsigned, col12 smallint unsigned, col13 int unsigned, col14 bigint unsigned)''')
+        for i in range(self.rowNum):
+            tdSql.execute("insert into ntb values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)
+        for i in range(self.rowNum):
+            tdSql.execute("insert into stb_1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d', %d, %d, %d, %d)" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1, i + 1, i + 1, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)  
+
+        tdSql.query("select timetruncate(1,1d) from ntb")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1u) from ntb")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1a) from ntb")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1m) from ntb")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1h) from ntb")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(ts,1d) from ntb")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 08:00:00.000")
+        tdSql.query("select timetruncate(ts,1h) from ntb")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.query("select timetruncate(ts,1m) from ntb")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.query("select timetruncate(ts,1s) from ntb")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.query("select timetruncate(ts,1a) from ntb")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.checkData(1,0,"2018-09-17 09:00:00.001")
+        tdSql.checkData(2,0,"2018-09-17 09:00:00.002")
+        tdSql.checkData(3,0,"2018-09-17 09:00:00.003")
+        tdSql.checkData(4,0,"2018-09-17 09:00:00.004")
+        tdSql.checkData(5,0,"2018-09-17 09:00:00.005")
+        tdSql.checkData(6,0,"2018-09-17 09:00:00.006")
+        tdSql.checkData(7,0,"2018-09-17 09:00:00.007")
+        tdSql.checkData(8,0,"2018-09-17 09:00:00.008")
+        tdSql.checkData(9,0,"2018-09-17 09:00:00.009")
+        # tdSql.query("select timetruncate(ts,1u) from ntb")
+        # tdSql.checkRows(10)
+        # tdSql.checkData(0,0,"2018-09-17 09:00:00.000000")
+        # tdSql.checkData(1,0,"2018-09-17 09:00:00.001000")
+        # tdSql.checkData(2,0,"2018-09-17 09:00:00.002000")
+        # tdSql.checkData(3,0,"2018-09-17 09:00:00.003000")
+        # tdSql.checkData(4,0,"2018-09-17 09:00:00.004000")
+        # tdSql.checkData(5,0,"2018-09-17 09:00:00.005000")
+        # tdSql.checkData(6,0,"2018-09-17 09:00:00.006000")
+        # tdSql.checkData(7,0,"2018-09-17 09:00:00.007000")
+        # tdSql.checkData(8,0,"2018-09-17 09:00:00.008000")
+        # tdSql.checkData(9,0,"2018-09-17 09:00:00.009000")
+        # tdSql.query("select timetruncate(ts,1b) from ntb")
+        # tdSql.checkRows(10)
+        # tdSql.checkData(0,0,"2018-09-17 09:00:00.000000000")
+        # tdSql.checkData(1,0,"2018-09-17 09:00:00.001000000")
+        # tdSql.checkData(2,0,"2018-09-17 09:00:00.002000000")
+        # tdSql.checkData(3,0,"2018-09-17 09:00:00.003000000")
+        # tdSql.checkData(4,0,"2018-09-17 09:00:00.004000000")
+        # tdSql.checkData(5,0,"2018-09-17 09:00:00.005000000")
+        # tdSql.checkData(6,0,"2018-09-17 09:00:00.006000000")
+        # tdSql.checkData(7,0,"2018-09-17 09:00:00.007000000")
+        # tdSql.checkData(8,0,"2018-09-17 09:00:00.008000000")
+        # tdSql.checkData(9,0,"2018-09-17 09:00:00.009000000")
+
+
+        tdSql.query("select timetruncate(1,1d) from stb")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1u) from stb")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1a) from stb")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1m) from stb")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1h) from stb")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(ts,1d) from stb")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 08:00:00.000")
+        tdSql.query("select timetruncate(ts,1h) from stb")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.query("select timetruncate(ts,1m) from stb")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.query("select timetruncate(ts,1s) from stb")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.query("select timetruncate(ts,1a) from stb")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.checkData(1,0,"2018-09-17 09:00:00.001")
+        tdSql.checkData(2,0,"2018-09-17 09:00:00.002")
+        tdSql.checkData(3,0,"2018-09-17 09:00:00.003")
+        tdSql.checkData(4,0,"2018-09-17 09:00:00.004")
+        tdSql.checkData(5,0,"2018-09-17 09:00:00.005")
+        tdSql.checkData(6,0,"2018-09-17 09:00:00.006")
+        tdSql.checkData(7,0,"2018-09-17 09:00:00.007")
+        tdSql.checkData(8,0,"2018-09-17 09:00:00.008")
+        tdSql.checkData(9,0,"2018-09-17 09:00:00.009")
+        # tdSql.query("select timetruncate(ts,1u) from stb")
+        # tdSql.checkRows(10)
+        # tdSql.checkData(0,0,"2018-09-17 09:00:00.000000")
+        # tdSql.checkData(1,0,"2018-09-17 09:00:00.001000")
+        # tdSql.checkData(2,0,"2018-09-17 09:00:00.002000")
+        # tdSql.checkData(3,0,"2018-09-17 09:00:00.003000")
+        # tdSql.checkData(4,0,"2018-09-17 09:00:00.004000")
+        # tdSql.checkData(5,0,"2018-09-17 09:00:00.005000")
+        # tdSql.checkData(6,0,"2018-09-17 09:00:00.006000")
+        # tdSql.checkData(7,0,"2018-09-17 09:00:00.007000")
+        # tdSql.checkData(8,0,"2018-09-17 09:00:00.008000")
+        # tdSql.checkData(9,0,"2018-09-17 09:00:00.009000")
+        # tdSql.query("select timetruncate(ts,1b) from stb")
+        # tdSql.checkRows(10)
+        # tdSql.checkData(0,0,"2018-09-17 09:00:00.000000000")
+        # tdSql.checkData(1,0,"2018-09-17 09:00:00.001000000")
+        # tdSql.checkData(2,0,"2018-09-17 09:00:00.002000000")
+        # tdSql.checkData(3,0,"2018-09-17 09:00:00.003000000")
+        # tdSql.checkData(4,0,"2018-09-17 09:00:00.004000000")
+        # tdSql.checkData(5,0,"2018-09-17 09:00:00.005000000")
+        # tdSql.checkData(6,0,"2018-09-17 09:00:00.006000000")
+        # tdSql.checkData(7,0,"2018-09-17 09:00:00.007000000")
+        # tdSql.checkData(8,0,"2018-09-17 09:00:00.008000000")
+        # tdSql.checkData(9,0,"2018-09-17 09:00:00.009000000")
+
+        tdSql.query("select timetruncate(1,1d) from stb_1")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1u) from stb_1")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1a) from stb_1")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1m) from stb_1")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(1,1h) from stb_1")
+        tdSql.checkRows(10)
+        tdSql.query("select timetruncate(ts,1d) from stb_1")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 08:00:00.000")
+        tdSql.query("select timetruncate(ts,1h) from stb_1")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.query("select timetruncate(ts,1m) from stb_1")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.query("select timetruncate(ts,1s) from stb_1")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.query("select timetruncate(ts,1a) from stb_1")
+        tdSql.checkRows(10)
+        tdSql.checkData(0,0,"2018-09-17 09:00:00.000")
+        tdSql.checkData(1,0,"2018-09-17 09:00:00.001")
+        tdSql.checkData(2,0,"2018-09-17 09:00:00.002")
+        tdSql.checkData(3,0,"2018-09-17 09:00:00.003")
+        tdSql.checkData(4,0,"2018-09-17 09:00:00.004")
+        tdSql.checkData(5,0,"2018-09-17 09:00:00.005")
+        tdSql.checkData(6,0,"2018-09-17 09:00:00.006")
+        tdSql.checkData(7,0,"2018-09-17 09:00:00.007")
+        tdSql.checkData(8,0,"2018-09-17 09:00:00.008")
+        tdSql.checkData(9,0,"2018-09-17 09:00:00.009")
+        # tdSql.query("select timetruncate(ts,1u) from stb_1")
+        # tdSql.checkRows(10)
+        # tdSql.checkData(0,0,"2018-09-17 09:00:00.000000")
+        # tdSql.checkData(1,0,"2018-09-17 09:00:00.001000")
+        # tdSql.checkData(2,0,"2018-09-17 09:00:00.002000")
+        # tdSql.checkData(3,0,"2018-09-17 09:00:00.003000")
+        # tdSql.checkData(4,0,"2018-09-17 09:00:00.004000")
+        # tdSql.checkData(5,0,"2018-09-17 09:00:00.005000")
+        # tdSql.checkData(6,0,"2018-09-17 09:00:00.006000")
+        # tdSql.checkData(7,0,"2018-09-17 09:00:00.007000")
+        # tdSql.checkData(8,0,"2018-09-17 09:00:00.008000")
+        # tdSql.checkData(9,0,"2018-09-17 09:00:00.009000")
+        # tdSql.query("select timetruncate(ts,1b) from stb_1")
+        # tdSql.checkRows(10)
+        # tdSql.checkData(0,0,"2018-09-17 09:00:00.000000000")
+        # tdSql.checkData(1,0,"2018-09-17 09:00:00.001000000")
+        # tdSql.checkData(2,0,"2018-09-17 09:00:00.002000000")
+        # tdSql.checkData(3,0,"2018-09-17 09:00:00.003000000")
+        # tdSql.checkData(4,0,"2018-09-17 09:00:00.004000000")
+        # tdSql.checkData(5,0,"2018-09-17 09:00:00.005000000")
+        # tdSql.checkData(6,0,"2018-09-17 09:00:00.006000000")
+        # tdSql.checkData(7,0,"2018-09-17 09:00:00.007000000")
+        # tdSql.checkData(8,0,"2018-09-17 09:00:00.008000000")
+        # tdSql.checkData(9,0,"2018-09-17 09:00:00.009000000")
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file
diff --git a/tests/system-test/fulltest.sh b/tests/system-test/fulltest.sh
index 51f1649cc862920c534a5b00f2ab383b80cefbc1..4149c2cd9dd0bf5b959c178913004359a5732af6 100755
--- a/tests/system-test/fulltest.sh
+++ b/tests/system-test/fulltest.sh
@@ -11,10 +11,18 @@ python3 ./test.py -f 0-others/taosShellNetChk.py
 python3 ./test.py -f 2-query/distinct.py
 python3 ./test.py -f 2-query/varchar.py
 
-#python3 ./test.py -f 2-query/timezone.py
+python3 ./test.py -f 2-query/timezone.py
 python3 ./test.py -f 2-query/Now.py
 python3 ./test.py -f 2-query/Today.py
+python3 ./test.py -f 2-query/max.py
+python3 ./test.py -f 2-query/min.py
+python3 ./test.py -f 2-query/count.py
+python3 ./test.py -f 2-query/last.py
+#python3 ./test.py -f 2-query/To_iso8601.py
+python3 ./test.py -f 2-query/To_unixtimestamp.py
+python3 ./test.py -f 2-query/timetruncate.py
 
+# python3 ./test.py -f 2-query/Timediff.py
 #python3 ./test.py -f 2-query/cast.py