diff --git a/tests/system-test/0-others/udfpy_main.py b/tests/system-test/0-others/udfpy_main.py
index 9cc329ca19..1b5a1bab38 100644
--- a/tests/system-test/0-others/udfpy_main.py
+++ b/tests/system-test/0-others/udfpy_main.py
@@ -252,8 +252,6 @@ class TDTestCase:
         self.verfiy_same_value(sql)
         sql = f'select sum(col9), af_sum_float(col9) from {self.stbname}'
         self.verfiy_same_value(sql)
-
-
             
     
     # insert to child table d1 data
@@ -266,6 +264,15 @@ class TDTestCase:
                 sql = f'insert into {tbname}{i} values({ts+j},{cols});' 
                 tdSql.execute(sql)
 
+        # partial columns upate
+        sql = f'insert into {tbname}0(ts, col1, col9, col11) values(now, 100, 200, 0)'
+        tdSql.execute(sql)
+        sql = f'insert into {tbname}0(ts, col2, col5, col8) values(now, 100, 200, 300)'
+        tdSql.execute(sql)
+        sql = f'insert into {tbname}0(ts, col3, col7, col13) values(now, null, null, null)'
+        tdSql.execute(sql)        
+        sql = f'insert into {tbname}0(ts) values(now)'
+        tdSql.execute(sql)
         tdLog.info(f" insert {rows} for each child table.")
 
 
@@ -288,8 +295,6 @@ class TDTestCase:
         self.query_aggr_udfpy()
 
 
-
-
     def stop(self):
         tdSql.close()
         tdLog.success("%s successfully executed" % __file__)