diff --git a/run_datatypes.sh b/run_datatypes.sh
index 2675ff4..fc4e9a3 100755
--- a/run_datatypes.sh
+++ b/run_datatypes.sh
@@ -2,7 +2,7 @@
 
 sudo bash -c "echo 1 > /proc/sys/net/ipv4/tcp_tw_reuse"
 
-python3 main.py \
+python3 main.py ${*:1} \
     --src-resume \
     --src-wait \
     --src-host=127.0.0.1 \
diff --git a/run_ontime.sh b/run_ontime.sh
index 292e442..520ad4a 100755
--- a/run_ontime.sh
+++ b/run_ontime.sh
@@ -2,10 +2,11 @@
 
 sudo bash -c "echo 1 > /proc/sys/net/ipv4/tcp_tw_reuse"
 
-python3.6 main.py \
+python3.6 main.py ${*:1} \
     --src-resume \
     --src-wait \
     --nice-pause=1 \
+    --log-level=info \
     --src-host=127.0.0.1 \
     --src-user=root \
     --dst-host=127.0.0.1 \
@@ -21,3 +22,4 @@ python3.6 main.py \
 #	--dst-schema=db
 #   --dst-table=datatypes
 #	--csvpool-keep-files
+#    --log-level=info \
diff --git a/src/event/event.py b/src/event/event.py
index f1e502c..fe4d7f8 100644
--- a/src/event/event.py
+++ b/src/event/event.py
@@ -10,6 +10,10 @@ class Event(object):
     # table name
     table = None
 
+    #for row in mysql_event.rows:
+    #    event.rows.append(row['values'])
+    mysql_event = None
+
     # {'id':1, 'col1':1}
     row = None
 
@@ -22,14 +26,33 @@ class Event(object):
     # ['id', 'col1', 'col2']
     fieldnames = None
 
-    def first(self):
-        if self.rows is None:
-            return self.row
+    _iter = None
+
+    def __iter__(self):
+        if self.mysql_event is not None:
+            self._iter = iter(self.mysql_event.rows)
+
+        elif self.row is not None:
+            self._iter = iter([self.row])
+
         else:
-            return self.rows[0]
+            self._iter = iter(self.rows)
+
+        return self
 
-    def all(self):
-        if self.rows is None:
-            return [self.row]
+    def __next__(self):
+        item = next(self._iter)
+
+        if self.mysql_event is not None:
+            return item['values']
         else:
-            return self.rows
+            return item
+
+    def column_names(self):
+        if self.mysql_event is not None:
+            return self.mysql_event.rows[0]['values'].keys()
+
+        if self.row is not None:
+            return self.row.keys()
+
+        return self.rows[0].keys()
diff --git a/src/reader/mysqlreader.py b/src/reader/mysqlreader.py
index ebb607a..f5589c5 100644
--- a/src/reader/mysqlreader.py
+++ b/src/reader/mysqlreader.py
@@ -87,9 +87,7 @@ def read(self):
                             event = Event()
                             event.schema = mysql_event.schema
                             event.table = mysql_event.table
-                            event.rows = []
-                            for row in mysql_event.rows:
-                                event.rows.append(row['values'])
+                            event.mysql_event = mysql_event
                             self.notify('WriteRowsEvent', event=event)
 
                         if self.subscribers('WriteRowsEvent.EachRow'):
diff --git a/src/writer/chwriter.py b/src/writer/chwriter.py
index c68a98e..cd307b3 100644
--- a/src/writer/chwriter.py
+++ b/src/writer/chwriter.py
@@ -42,12 +42,12 @@ def insert(self, event_or_events=None):
 
         logging.debug('class:%s insert %d rows', __class__, len(events))
 
-        values = []
+        rows = []
         event_converted = None
         for event in events:
             event_converted = self.convert(event)
-            for value in event_converted.all():
-                values.append(value)
+            for row in event_converted:
+                rows.append(row)
 
         schema = self.dst_schema if self.dst_schema else event_converted.schema
         table = self.dst_table if self.dst_table else event_converted.table
@@ -56,13 +56,13 @@ def insert(self, event_or_events=None):
             sql = 'INSERT INTO `{0}`.`{1}` ({2}) VALUES'.format(
                 schema,
                 table,
-                ', '.join(map(lambda column: '`%s`' % column, values[0].keys()))
+                ', '.join(map(lambda column: '`%s`' % column, rows[0].keys()))
             )
-            self.client.execute(sql, values)
+            self.client.execute(sql, rows)
         except:
             print('QUERY FAILED -------------------------')
             print(sql)
-            print(values)
+            print(rows)
 
 
 if __name__ == '__main__':
diff --git a/src/writer/csvwriter.py b/src/writer/csvwriter.py
index 6e70f56..2074683 100644
--- a/src/writer/csvwriter.py
+++ b/src/writer/csvwriter.py
@@ -79,7 +79,7 @@ def insert(self, event_or_events):
             self.open()
 
         if not self.writer:
-            self.fieldnames = sorted(events[0].first().keys())
+            self.fieldnames = sorted(events[0].column_names())
             if self.dst_schema is None:
                 self.dst_schema = events[0].schema
             if self.dst_table is None:
@@ -90,7 +90,7 @@ def insert(self, event_or_events):
                 self.writer.writeheader()
 
         for event in events:
-            for row in event.all():
+            for row in event:
                 self.writer.writerow(self.convert(row))
 
     def push(self):