diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1c130e6..2ca1d84 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,7 +8,7 @@ Unreleased
 - Distributed engine support (tsionyx)
 - `_fields` and `_writable_fields` are OrderedDicts - note that this might break backwards compatibility (tsionyx)
 - Improve error messages returned from the database with the `ServerError` class (tsionyx)
-- Added support of custom partitioning (M1hacka)
+- Added support for custom partitioning (M1hacka)
 - Added attribute `server_version` to Database class (M1hacka)
 - Changed `Engine.create_table_sql()`, `Engine.drop_table_sql()`, `Model.create_table_sql()`, `Model.drop_table_sql()` parameter to db from db_name (M1hacka)
 - Fix parsing of datetime column type when it includes a timezone (M1hacka)
diff --git a/docs/class_reference.md b/docs/class_reference.md
index edcf4f9..637fbc9 100644
--- a/docs/class_reference.md
+++ b/docs/class_reference.md
@@ -695,21 +695,21 @@ straightly into Distributed table, optional
 
 Extends MergeTree
 
-#### CollapsingMergeTree(date_col, order_by, sign_col, sampling_expr=None, index_granularity=8192, replica_table_path=None, replica_name=None)
+#### CollapsingMergeTree(date_col=None, order_by=(), sign_col="sign", sampling_expr=None, index_granularity=8192, replica_table_path=None, replica_name=None, partition_key=None)
 
 
 ### SummingMergeTree
 
 Extends MergeTree
 
-#### SummingMergeTree(date_col, order_by, summing_cols=None, sampling_expr=None, index_granularity=8192, replica_table_path=None, replica_name=None)
+#### SummingMergeTree(date_col=None, order_by=(), summing_cols=None, sampling_expr=None, index_granularity=8192, replica_table_path=None, replica_name=None, partition_key=None)
 
 
 ### ReplacingMergeTree
 
 Extends MergeTree
 
-#### ReplacingMergeTree(date_col, order_by, ver_col=None, sampling_expr=None, index_granularity=8192, replica_table_path=None, replica_name=None)
+#### ReplacingMergeTree(date_col=None, order_by=(), ver_col=None, sampling_expr=None, index_granularity=8192, replica_table_path=None, replica_name=None, partition_key=None)
 
 
 infi.clickhouse_orm.query