diff --git a/dtable_events/tests/sql/test_reference.py b/dtable_events/tests/sql/test_reference.py
index 0eba2a9b..85083a56 100644
--- a/dtable_events/tests/sql/test_reference.py
+++ b/dtable_events/tests/sql/test_reference.py
@@ -266,7 +266,7 @@ def get_expected_sql_for_modifier(filter_modifier, column_name):
             "filter_predicate": 'And',
             "sorts":[],
         },
-        "expected_sql": "SELECT * FROM `Table1` WHERE `createTime` <= '2021-12-20' and `createTime` is not null LIMIT 0, 100",
+        "expected_sql": "SELECT * FROM `Table1` WHERE `createTime` < '2021-12-21' and `createTime` is not null LIMIT 0, 100",
         "by_group": False,
     },
     {
diff --git a/dtable_events/utils/sql_generator.py b/dtable_events/utils/sql_generator.py
index 5c9db79c..c53ea16c 100644
--- a/dtable_events/utils/sql_generator.py
+++ b/dtable_events/utils/sql_generator.py
@@ -846,9 +846,11 @@ def op_is_on_or_before(self):
         target_date, _ = self._other_date()
         if not target_date:
             return ""
-        return "`%(column_name)s` <= '%(target_date)s' and `%(column_name)s` is not null" % ({
+
+        next_date = self._format_date(target_date + timedelta(days=1))
+        return "`%(column_name)s` < '%(target_date)s' and `%(column_name)s` is not null" % ({
             "column_name": self.column_name,
-            "target_date": self._format_date(target_date)
+            "target_date": next_date
         })
 
     def op_is_on_or_after(self):