diff --git a/CHANGELOG.md b/CHANGELOG.md
index c68e010adf..366e010803 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -66,6 +66,17 @@
 - Fixed a bug where `pd.to_numeric()` would leave `Timedelta` inputs as `Timedelta` instead of converting them to integers.
 - Fixed `loc` set when setting a single row, or multiple rows, of a DataFrame with a Series value.
 
+### Snowpark Local Testing Updates
+
+#### Bug Fixes
+
+- Fixed a bug where nullable columns were annotated wrongly.
+- Fixed a bug where the `date_add` and `date_sub` functions failed for `NULL` values.
+- Fixed a bug where `equal_null` could fail inside a merge statement.
+- Fixed a bug where `row_number` could fail inside a Window function.
+- Fixed a bug where updates could fail when the source is the result of a join.
+
+
 ## 1.22.1 (2024-09-11)
 This is a re-release of 1.22.0. Please refer to the 1.22.0 release notes for detailed release content.
 
diff --git a/src/snowflake/snowpark/mock/_functions.py b/src/snowflake/snowpark/mock/_functions.py
index 3842f6fda3..ef469cec91 100644
--- a/src/snowflake/snowpark/mock/_functions.py
+++ b/src/snowflake/snowpark/mock/_functions.py
@@ -1530,6 +1530,8 @@ def add_months(scalar, date, duration):
 
 
 def add_timedelta(unit, date, duration, scalar=1):
+    if date is None:
+        return date
     return date + datetime.timedelta(**{f"{unit}s": float(duration) * scalar})
 
 
diff --git a/src/snowflake/snowpark/mock/_plan.py b/src/snowflake/snowpark/mock/_plan.py
index 5e8ae3f07a..d1fc060fb0 100644
--- a/src/snowflake/snowpark/mock/_plan.py
+++ b/src/snowflake/snowpark/mock/_plan.py
@@ -1293,7 +1293,7 @@ def outer_join(base_df):
             join_condition = calculate_expression(
                 source_plan.join_expr, cartesian_product, analyzer, expr_to_alias
             )
-            join_result = cartesian_product[join_condition]
+            join_result = cartesian_product[join_condition].reset_index(drop=True)
             join_result.sf_types = cartesian_product.sf_types
 
             # TODO [GA]: # ERROR_ON_NONDETERMINISTIC_MERGE is by default True, raise error if
@@ -1715,7 +1715,7 @@ def calculate_expression(
                 exp.datatype = StringType(len(exp.value))
             res = ColumnEmulator(
                 data=[exp.value for _ in range(len(input_data))],
-                sf_type=ColumnType(exp.datatype, False),
+                sf_type=ColumnType(exp.datatype, nullable=exp.value is None),
                 dtype=object,
             )
             res.index = input_data.index
@@ -2005,8 +2005,10 @@ def _match_pattern(row) -> bool:
 
         # Process partition_by clause
         if window_spec.partition_spec:
+            # Remove duplicate keys while maintaining order
+            keys = list(dict.fromkeys([exp.name for exp in window_spec.partition_spec]))
             res = res.groupby(
-                [exp.name for exp in window_spec.partition_spec],
+                keys,
                 sort=False,
                 as_index=False,
             )
@@ -2033,10 +2035,14 @@ def _match_pattern(row) -> bool:
                 indexer = EntireWindowIndexer()
                 rolling = res.rolling(indexer)
                 windows = [ordered.loc[w.index] for w in rolling]
+                # rolling can unpredictably change the index of the data
+                # apply a trivial function to materialize the final index
+                res_index = list(rolling.count().index)
 
         elif isinstance(window_spec.frame_spec.frame_type, RowFrame):
             indexer = RowFrameIndexer(frame_spec=window_spec.frame_spec)
             res = res.rolling(indexer)
+            res_index = list(res.count().index)
             windows = [w for w in res]
 
         elif isinstance(window_spec.frame_spec.frame_type, RangeFrame):
@@ -2066,6 +2072,7 @@ def _match_pattern(row) -> bool:
                 isinstance(lower, UnboundedPreceding),
                 isinstance(upper, UnboundedFollowing),
             )
+
         # compute window function:
         if isinstance(window_function, (FunctionExpression,)):
             res_cols = []
diff --git a/tests/integ/scala/test_dataframe_writer_suite.py b/tests/integ/scala/test_dataframe_writer_suite.py
index 275f32e955..3d6a6ff689 100644
--- a/tests/integ/scala/test_dataframe_writer_suite.py
+++ b/tests/integ/scala/test_dataframe_writer_suite.py
@@ -11,7 +11,7 @@
 from snowflake.snowpark import Row
 from snowflake.snowpark._internal.utils import TempObjectType, parse_table_name
 from snowflake.snowpark.exceptions import SnowparkSQLException
-from snowflake.snowpark.functions import col, parse_json
+from snowflake.snowpark.functions import col, lit, parse_json
 from snowflake.snowpark.mock.exceptions import SnowparkLocalTestingException
 from snowflake.snowpark.types import (
     DoubleType,
@@ -89,6 +89,17 @@ def test_write_with_target_column_name_order(session, local_testing_mode):
             Utils.drop_table(session, special_table_name)
 
 
+def test_snow_1668862_repro_save_null_data(session):
+    table_name = Utils.random_table_name()
+    test_data = session.create_dataframe([(1,), (2,)], ["A"])
+    df = test_data.with_column("b", lit(None))
+    try:
+        df.write.save_as_table(table_name=table_name, mode="truncate")
+        assert session.table(table_name).collect() == [Row(1, None), Row(2, None)]
+    finally:
+        Utils.drop_table(session, table_name)
+
+
 def test_write_truncate_with_less_columns(session):
     # test truncate mode saving dataframe with fewer columns than the target table but column name in the same order
     schema1 = StructType(
diff --git a/tests/integ/scala/test_update_delete_merge_suite.py b/tests/integ/scala/test_update_delete_merge_suite.py
index c0afd3356d..41d195a15d 100644
--- a/tests/integ/scala/test_update_delete_merge_suite.py
+++ b/tests/integ/scala/test_update_delete_merge_suite.py
@@ -8,6 +8,7 @@
 
 import pytest
 
+from snowflake.connector.options import installed_pandas, pandas as pd
 from snowflake.snowpark import (
     DeleteResult,
     MergeResult,
@@ -21,6 +22,7 @@
 from snowflake.snowpark.exceptions import SnowparkTableException
 from snowflake.snowpark.functions import (
     col,
+    lit,
     max as max_,
     mean,
     min as min_,
@@ -668,3 +670,27 @@ def test_merge_multi_operation(session):
         ],
     )
     assert target.sort(col("id")).collect() == [Row(1, "a")]
+
+
+@pytest.mark.skipif(
+    not installed_pandas,
+    reason="Test requires pandas.",
+)
+def test_snow_1694649_repro_merge_with_equal_null(session):
+    # Force temp table
+    df1 = session.create_dataframe(pd.DataFrame({"A": [0, 1], "B": ["a", "b"]}))
+    df2 = session.create_dataframe(pd.DataFrame({"A": [0, 1], "B": ["a", "c"]}))
+
+    df1.merge(
+        source=df2,
+        join_expr=df1["A"].equal_null(df2["A"]),
+        clauses=[
+            when_matched(
+                ~(df1["A"].equal_null(df2["A"])) & (df1["B"].equal_null(df2["B"]))
+            ).update({"A": lit(3)})
+        ],
+    )
+    assert session.table(df1.table_name).order_by("A").collect() == [
+        Row(0, "a"),
+        Row(1, "b"),
+    ]
diff --git a/tests/integ/scala/test_window_spec_suite.py b/tests/integ/scala/test_window_spec_suite.py
index 217100cca1..c2bb91360b 100644
--- a/tests/integ/scala/test_window_spec_suite.py
+++ b/tests/integ/scala/test_window_spec_suite.py
@@ -3,6 +3,7 @@
 # Copyright (c) 2012-2024 Snowflake Computing Inc. All rights reserved.
 #
 
+from datetime import date
 from decimal import Decimal
 
 import pytest
@@ -274,6 +275,30 @@ def test_window_function_should_fail_if_order_by_clause_is_not_specified(session
     assert "requires ORDER BY in window specification" in str(ex_info)
 
 
+def test_snow_1360263_repro(session):
+    data = [
+        Row(id=1, row_date=date(2024, 1, 1), value=1),
+        Row(id=2, row_date=date(2024, 1, 1), value=1),
+        Row(id=1, row_date=date(2024, 1, 2), value=1),
+        Row(id=1, row_date=date(2024, 1, 2), value=100),
+        Row(id=2, row_date=date(2024, 1, 2), value=1),
+    ]
+
+    test_data = session.create_dataframe(data)
+
+    # partition over id and row_date and get the records with the largest values
+    window = Window.partition_by("id", "row_date").order_by(col("value").desc())
+    df = test_data.with_column("row_num", row_number().over(window)).where(
+        col("row_num") == 1
+    )
+    assert df.order_by("ID", "ROW_DATE").collect() == [
+        Row(1, date(2024, 1, 1), 1, 1),
+        Row(1, date(2024, 1, 2), 100, 1),
+        Row(2, date(2024, 1, 1), 1, 1),
+        Row(2, date(2024, 1, 2), 1, 1),
+    ]
+
+
 @pytest.mark.skipif(
     "config.getoption('local_testing_mode', default=False)",
     reason="corr is not yet supported in local testing mode.",
diff --git a/tests/integ/test_function.py b/tests/integ/test_function.py
index 070f57d45a..5797d11fbe 100644
--- a/tests/integ/test_function.py
+++ b/tests/integ/test_function.py
@@ -1816,17 +1816,27 @@ def test_date_operations_negative(session):
 
 def test_date_add_date_sub(session):
     df = session.createDataFrame(
-        [("2019-01-23"), ("2019-06-24"), ("2019-09-20")], ["date"]
+        [
+            ("2019-01-23"),
+            ("2019-06-24"),
+            ("2019-09-20"),
+            (None),
+        ],
+        ["date"],
     )
     df = df.withColumn("date", to_date("date"))
-    res = df.withColumn("date", date_add("date", 4)).collect()
-    assert res[0].DATE == datetime.date(2019, 1, 27)
-    assert res[1].DATE == datetime.date(2019, 6, 28)
-    assert res[2].DATE == datetime.date(2019, 9, 24)
-    res = df.withColumn("date", date_sub("date", 4)).collect()
-    assert res[0].DATE == datetime.date(2019, 1, 19)
-    assert res[1].DATE == datetime.date(2019, 6, 20)
-    assert res[2].DATE == datetime.date(2019, 9, 16)
+    assert df.withColumn("date", date_add("date", 4)).collect() == [
+        Row(datetime.date(2019, 1, 27)),
+        Row(datetime.date(2019, 6, 28)),
+        Row(datetime.date(2019, 9, 24)),
+        Row(None),
+    ]
+    assert df.withColumn("date", date_sub("date", 4)).collect() == [
+        Row(datetime.date(2019, 1, 19)),
+        Row(datetime.date(2019, 6, 20)),
+        Row(datetime.date(2019, 9, 16)),
+        Row(None),
+    ]
 
 
 @pytest.mark.skipif(