Merge branch 'custom_partitioning' of https://github.com/carrotquest/infi.clickhouse_orm into carrotquest-custom_partitioning

# Conflicts:
#	src/infi/clickhouse_orm/engines.py
#	src/infi/clickhouse_orm/models.py
#	tests/test_database.py
#	tests/test_engines.py

docs/class_reference.md

@@ -24,6 +24,18 @@ created on the ClickHouse server if it does not already exist.
 - `autocreate`: automatically create the database if does not exist (unless in readonly mode).
 
 
+#### server_timezone
+
+
+Contains [pytz](http://pytz.sourceforge.net/) timezone used on database server
+
+
+#### server_version
+
+
+Contains a version tuple of database server, for example (1, 1, 54310)
+
+
 #### count(model_class, conditions=None)
 
 
@@ -144,13 +156,13 @@ invalid values will cause a `ValueError` to be raised.
 Unrecognized field names will cause an `AttributeError`.
 
 
-#### Model.create_table_sql(db_name)
+#### Model.create_table_sql(db)
 
 
 Returns the SQL command for creating a table for this model.
 
 
-#### Model.drop_table_sql(db_name)
+#### Model.drop_table_sql(db)
 
 
 Returns the SQL command for deleting this model's table.
@@ -241,13 +253,13 @@ invalid values will cause a `ValueError` to be raised.
 Unrecognized field names will cause an `AttributeError`.
 
 
-#### BufferModel.create_table_sql(db_name)
+#### BufferModel.create_table_sql(db)
 
 
 Returns the SQL command for creating a table for this model.
 
 
-#### BufferModel.drop_table_sql(db_name)
+#### BufferModel.drop_table_sql(db)
 
 
 Returns the SQL command for deleting this model's table.
@@ -639,7 +651,7 @@ Extends Engine
 
 Extends Engine
 
-#### MergeTree(date_col, key_cols, sampling_expr=None, index_granularity=8192, replica_table_path=None, replica_name=None)
+#### MergeTree(date_col=None, order_by=(), sampling_expr=None, index_granularity=8192, replica_table_path=None, replica_name=None, partition_key=None)
 
 
 ### Buffer

docs/ref.md

@@ -119,12 +119,12 @@ invalid values will cause a `ValueError` to be raised.
 Unrecognized field names will cause an `AttributeError`.
 
 
-#### Model.create_table_sql(db_name)
+#### Model.create_table_sql(db)
 
 Returns the SQL command for creating a table for this model.
 
 
-#### Model.drop_table_sql(db_name)
+#### Model.drop_table_sql(db)
 
 Returns the SQL command for deleting this model's table.
 
@@ -197,12 +197,12 @@ invalid values will cause a `ValueError` to be raised.
 Unrecognized field names will cause an `AttributeError`.
 
 
-#### BufferModel.create_table_sql(db_name)
+#### BufferModel.create_table_sql(db)
 
 Returns the SQL command for creating a table for this model.
 
 
-#### BufferModel.drop_table_sql(db_name)
+#### BufferModel.drop_table_sql(db)
 
 Returns the SQL command for deleting this model's table.
 

docs/table_engines.md

@@ -55,6 +55,23 @@ For a `ReplacingMergeTree` you can optionally specify the version column:
 
     engine = engines.ReplacingMergeTree('EventDate', ('OrderID', 'EventDate', 'BannerID'), ver_col='Version')
 
+### Custom partitioning
+
+ClickHouse supports [custom partitioning](https://clickhouse.yandex/docs/en/table_engines/custom_partitioning_key/) expressions since version 1.1.54310
+You can use custom partitioning with any MergeTree family engine.
+To set custom partitioning:
+* skip date_col (first) constructor parameter or fill it with None value
+* add name to order_by (second) constructor parameter
+* add partition_key parameter. It should be a tuple of expressions, by which partition are built.
+
+Standard partitioning by date column can be added using toYYYYMM(date) function.
+
+Example:
+ 
+    engine = engines.ReplacingMergeTree(order_by=('OrderID', 'EventDate', 'BannerID'), ver_col='Version',
+                                        partition_key=('toYYYYMM(EventDate)', 'BannerID'))
+
+
 ### Data Replication
 
 Any of the above engines can be converted to a replicated engine (e.g. `ReplicatedMergeTree`) by adding two parameters, `replica_table_path` and `replica_name`:

src/infi/clickhouse_orm/database.py

@@ -97,6 +97,7 @@ class Database(object):
             self.db_exists = False
             self.create_database()
         self.server_timezone = self._get_server_timezone()
+        self.server_version = self._get_server_version()
 
     def create_database(self):
         '''
@@ -118,7 +119,7 @@ class Database(object):
         # TODO check that model has an engine
         if model_class.system:
             raise DatabaseException("You can't create system table")
-        self._send(model_class.create_table_sql(self.db_name))
+        self._send(model_class.create_table_sql(self))
 
     def drop_table(self, model_class):
         '''
@@ -126,7 +127,7 @@ class Database(object):
         '''
         if model_class.system:
             raise DatabaseException("You can't drop system table")
-        self._send(model_class.drop_table_sql(self.db_name))
+        self._send(model_class.drop_table_sql(self))
 
     def insert(self, model_instances, batch_size=1000):
         '''
@@ -326,6 +327,11 @@ class Database(object):
             logger.exception('Cannot determine server timezone (%s), assuming UTC', e)
             return pytz.utc
 
+    def _get_server_version(self, as_tuple=True):
+        r = self._send('SELECT version();')
+        ver = r.text
+        return tuple(int(n) for n in ver.split('.')) if as_tuple else ver
+
     def _is_connection_readonly(self):
         r = self._send("SELECT value FROM system.settings WHERE name = 'readonly'")
         return r.text.strip() != '0'

src/infi/clickhouse_orm/engines.py

@@ -1,89 +1,141 @@
 from __future__ import unicode_literals
 
+import logging
 import six
 
 from .utils import comma_join
 
+logger = logging.getLogger('clickhouse_orm')
+
 
 class Engine(object):
 
-    def create_table_sql(self):
+    def create_table_sql(self, db):
         raise NotImplementedError()   # pragma: no cover
 
 
 class TinyLog(Engine):
 
-    def create_table_sql(self):
+    def create_table_sql(self, db):
         return 'TinyLog'
 
 
 class Log(Engine):
 
-    def create_table_sql(self):
+    def create_table_sql(self, db):
         return 'Log'
 
 
 class Memory(Engine):
 
-    def create_table_sql(self):
+    def create_table_sql(self, db):
         return 'Memory'
 
 
 class MergeTree(Engine):
 
-    def __init__(self, date_col, key_cols, sampling_expr=None,
+    def __init__(self, date_col=None, order_by=(), sampling_expr=None,
-                 index_granularity=8192, replica_table_path=None, replica_name=None):
+                 index_granularity=8192, replica_table_path=None, replica_name=None, partition_key=None):
-        assert type(key_cols) in (list, tuple), 'key_cols must be a list or tuple'
+        assert type(order_by) in (list, tuple), 'order_by must be a list or tuple'
+        assert date_col is None or isinstance(date_col, six.string_types), 'date_col must be string if present'
+        assert partition_key is None or type(partition_key) in (list, tuple),\
+            'partition_key must be tuple or list if present'
+
+        # These values conflict with each other (old and new syntax of table engines.
+        # So let's control only one of them is given.
+        assert date_col or partition_key, "You must set either date_col or partition_key"
         self.date_col = date_col
-        self.key_cols = key_cols
+        self.partition_key = partition_key if partition_key else ('toYYYYMM(`%s`)' % date_col,)
+
+        self.order_by = order_by
         self.sampling_expr = sampling_expr
         self.index_granularity = index_granularity
         self.replica_table_path = replica_table_path
         self.replica_name = replica_name
         # TODO verify that both replica fields are either present or missing
 
-    def create_table_sql(self):
+    # I changed field name for new reality and syntax
+    @property
+    def key_cols(self):
+        logger.warning('`key_cols` attribute is deprecated and may be removed in future. Use `order_by` attribute instead')
+        return self.order_by
+
+    @key_cols.setter
+    def key_cols(self, value):
+        logger.warning('`key_cols` attribute is deprecated and may be removed in future. Use `order_by` attribute instead')
+        self.order_by = value
+
+    def create_table_sql(self, db):
         name = self.__class__.__name__
         if self.replica_name:
             name = 'Replicated' + name
-        params = self._build_sql_params()
-        return '%s(%s)' % (name, comma_join(params))
 
-    def _build_sql_params(self):
+        # In ClickHouse 1.1.54310 custom partitioning key was introduced
+        # https://clickhouse.yandex/docs/en/table_engines/custom_partitioning_key/
+        # Let's check version and use new syntax if available
+        if db.server_version >= (1, 1, 54310):
+            partition_sql = "PARTITION BY %s ORDER BY %s" \
+                            % ('(%s)' % comma_join(self.partition_key), '(%s)' % comma_join(self.order_by))
+
+            if self.sampling_expr:
+                partition_sql += " SAMPLE BY %s" % self.sampling_expr
+
+            partition_sql += " SETTINGS index_granularity=%d" % self.index_granularity
+
+        elif not self.date_col:
+            # Can't import it globally due to circular import
+            from infi.clickhouse_orm.database import DatabaseException
+            raise DatabaseException("Custom partitioning is not supported before ClickHouse 1.1.54310. "
+                                    "Please update your server or use date_col syntax."
+                                    "https://clickhouse.yandex/docs/en/table_engines/custom_partitioning_key/")
+        else:
+            partition_sql = ''
+
+        params = self._build_sql_params(db)
+        return '%s(%s) %s' % (name, comma_join(params), partition_sql)
+
+    def _build_sql_params(self, db):
         params = []
         if self.replica_name:
             params += ["'%s'" % self.replica_table_path, "'%s'" % self.replica_name]
-        params.append(self.date_col)
+
-        if self.sampling_expr:
+        # In ClickHouse 1.1.54310 custom partitioning key was introduced
-            params.append(self.sampling_expr)
+        # https://clickhouse.yandex/docs/en/table_engines/custom_partitioning_key/
-        params.append('(%s)' % comma_join(self.key_cols))
+        # These parameters are process in create_table_sql directly.
-        params.append(str(self.index_granularity))
+        # In previous ClickHouse versions this this syntax does not work.
+        if db.server_version < (1, 1, 54310):
+            params.append(self.date_col)
+            if self.sampling_expr:
+                params.append(self.sampling_expr)
+            params.append('(%s)' % comma_join(self.order_by))
+            params.append(str(self.index_granularity))
+
         return params
 
 
 class CollapsingMergeTree(MergeTree):
 
-    def __init__(self, date_col, key_cols, sign_col, sampling_expr=None,
+    def __init__(self, date_col, order_by, sign_col, sampling_expr=None,
                  index_granularity=8192, replica_table_path=None, replica_name=None):
-        super(CollapsingMergeTree, self).__init__(date_col, key_cols, sampling_expr, index_granularity, replica_table_path, replica_name)
+        super(CollapsingMergeTree, self).__init__(date_col, order_by, sampling_expr, index_granularity, replica_table_path, replica_name)
         self.sign_col = sign_col
 
-    def _build_sql_params(self):
+    def _build_sql_params(self, db):
-        params = super(CollapsingMergeTree, self)._build_sql_params()
+        params = super(CollapsingMergeTree, self)._build_sql_params(db)
         params.append(self.sign_col)
         return params
 
 
 class SummingMergeTree(MergeTree):
 
-    def __init__(self, date_col, key_cols, summing_cols=None, sampling_expr=None,
+    def __init__(self, date_col, order_by, summing_cols=None, sampling_expr=None,
                  index_granularity=8192, replica_table_path=None, replica_name=None):
-        super(SummingMergeTree, self).__init__(date_col, key_cols, sampling_expr, index_granularity, replica_table_path, replica_name)
+        super(SummingMergeTree, self).__init__(date_col, order_by, sampling_expr, index_granularity, replica_table_path, replica_name)
         assert type is None or type(summing_cols) in (list, tuple), 'summing_cols must be a list or tuple'
         self.summing_cols = summing_cols
 
-    def _build_sql_params(self):
+    def _build_sql_params(self, db):
-        params = super(SummingMergeTree, self)._build_sql_params()
+        params = super(SummingMergeTree, self)._build_sql_params(db)
         if self.summing_cols:
             params.append('(%s)' % comma_join(self.summing_cols))
         return params
@@ -91,13 +143,13 @@ class SummingMergeTree(MergeTree):
 
 class ReplacingMergeTree(MergeTree):
 
-    def __init__(self, date_col, key_cols, ver_col=None, sampling_expr=None,
+    def __init__(self, date_col, order_by, ver_col=None, sampling_expr=None,
                  index_granularity=8192, replica_table_path=None, replica_name=None):
-        super(ReplacingMergeTree, self).__init__(date_col, key_cols, sampling_expr, index_granularity, replica_table_path, replica_name)
+        super(ReplacingMergeTree, self).__init__(date_col, order_by, sampling_expr, index_granularity, replica_table_path, replica_name)
         self.ver_col = ver_col
 
-    def _build_sql_params(self):
+    def _build_sql_params(self, db):
-        params = super(ReplacingMergeTree, self)._build_sql_params()
+        params = super(ReplacingMergeTree, self)._build_sql_params(db)
         if self.ver_col:
             params.append(self.ver_col)
         return params
@@ -121,11 +173,11 @@ class Buffer(Engine):
         self.min_bytes = min_bytes
         self.max_bytes = max_bytes
 
-    def create_table_sql(self, db_name):
+    def create_table_sql(self, db):
         # Overriden create_table_sql example:
-        #sql = 'ENGINE = Buffer(merge, hits, 16, 10, 100, 10000, 1000000, 10000000, 100000000)'
+        # sql = 'ENGINE = Buffer(merge, hits, 16, 10, 100, 10000, 1000000, 10000000, 100000000)'
         sql = 'ENGINE = Buffer(`%s`, `%s`, %d, %d, %d, %d, %d, %d, %d)' % (
-                   db_name, self.main_model.table_name(), self.num_layers,
+                   db.db_name, self.main_model.table_name(), self.num_layers,
                    self.min_time, self.max_time, self.min_rows,
                    self.max_rows, self.min_bytes, self.max_bytes
               )
@@ -142,19 +194,10 @@ class Merge(Engine):
 
     def __init__(self, table_regex):
         assert isinstance(table_regex, six.string_types), "'table_regex' parameter must be string"
-
         self.table_regex = table_regex
 
-        # Use current database as default
+    def create_table_sql(self, db):
-        self.db_name = None
+        self.db_name = None + return "Merge(`%s`, '%s')" % (db.db_name, self.table_regex)
-
-    def create_table_sql(self):
-        db_name = ("`%s`" % self.db_name) if self.db_name else 'currentDatabase()'
-        return "Merge(%s, '%s')" % (db_name, self.table_regex)
-
-    def set_db_name(self, db_name):
-        assert isinstance(db_name, six.string_types), "'db_name' parameter must be string"
-        self.db_name = db_name
 
 
 class Distributed(Engine):

src/infi/clickhouse_orm/models.py

@@ -173,25 +173,25 @@ class Model(with_metaclass(ModelBase)):
         return cls.__name__.lower()
 
     @classmethod
-    def create_table_sql(cls, db_name):
+    def create_table_sql(cls, db):
         '''
         Returns the SQL command for creating a table for this model.
         '''
-        parts = ['CREATE TABLE IF NOT EXISTS `%s`.`%s` (' % (db_name, cls.table_name())]
+        parts = ['CREATE TABLE IF NOT EXISTS `%s`.`%s` (' % (db.db_name, cls.table_name())]
         cols = []
         for name, field in iteritems(cls.fields()):
             cols.append('    %s %s' % (name, field.get_sql()))
         parts.append(',\n'.join(cols))
         parts.append(')')
-        parts.append('ENGINE = ' + cls.engine.create_table_sql())
+        parts.append('ENGINE = ' + cls.engine.create_table_sql(db))
         return '\n'.join(parts)
 
     @classmethod
-    def drop_table_sql(cls, db_name):
+    def drop_table_sql(cls, db):
         '''
         Returns the SQL command for deleting this model's table.
         '''
-        return 'DROP TABLE IF EXISTS `%s`.`%s`' % (db_name, cls.table_name())
+        return 'DROP TABLE IF EXISTS `%s`.`%s`' % (db.db_name, cls.table_name())
 
     @classmethod
     def from_tsv(cls, line, field_names=None, timezone_in_use=pytz.utc, database=None):
@@ -265,12 +265,13 @@ class Model(with_metaclass(ModelBase)):
 class BufferModel(Model):
 
     @classmethod
-    def create_table_sql(cls, db_name):
+    def create_table_sql(cls, db):
         '''
         Returns the SQL command for creating a table for this model.
         '''
-        parts = ['CREATE TABLE IF NOT EXISTS `%s`.`%s` AS `%s`.`%s`' % (db_name, cls.table_name(), db_name, cls.engine.main_model.table_name())]
+        parts = ['CREATE TABLE IF NOT EXISTS `%s`.`%s` AS `%s`.`%s`' % (db.db_name, cls.table_name(), db.db_name,
-        engine_str = cls.engine.create_table_sql(db_name)
+                                                                        cls.engine.main_model.table_name())]
+        engine_str = cls.engine.create_table_sql(db)
         parts.append(engine_str)
         return ' '.join(parts)
 
@@ -286,21 +287,10 @@ class MergeModel(Model):
     # Virtual fields can't be inserted into database
     _table = StringField(readonly=True)
 
-    def set_database(self, db):
-        '''
-        Gets the `Database` that this model instance belongs to.
-        Returns `None` unless the instance was read from the database or written to it.
-        '''
-        assert isinstance(self.engine, Merge), "engine must be engines.Merge instance"
-        res = super(MergeModel, self).set_database(db)
-        self.engine.set_db_name(db.db_name)
-        return res
-
     @classmethod
-    def create_table_sql(cls, db_name):
+    def create_table_sql(cls, db):
         assert isinstance(cls.engine, Merge), "engine must be engines.Merge instance"
-        cls.engine.set_db_name(db_name)
+        return super(MergeModel, cls).create_table_sql(db)
-        return super(MergeModel, cls).create_table_sql(db_name)
 
 
 # TODO: base class for models that require specific engine
@@ -380,3 +370,5 @@ class DistributedModel(Model):
                 db_name, cls.table_name(), cls.engine.table_name),
             'ENGINE = ' + cls.engine.create_table_sql()]
         return '\n'.join(parts)
+        cls.engine.set_db_name(db_name)
+        return super(MergeModel, cls).create_table_sql(db_name)

src/infi/clickhouse_orm/system_models.py

@@ -68,7 +68,8 @@ class SystemPart(Model):
         """
         operation = operation.upper()
         assert operation in self.OPERATIONS, "operation must be in [%s]" % comma_join(self.OPERATIONS)
-        sql = "ALTER TABLE `%s`.`%s` %s PARTITION '%s'" % (self._database.db_name, self.table, operation, self.partition)
+
+        sql = "ALTER TABLE `%s`.`%s` %s PARTITION %s" % (self._database.db_name, self.table, operation, self.partition)
         if from_part is not None:
             sql += " FROM %s" % from_part
         self._database.raw(sql, settings=settings, stream=False)

tests/test_engines.py

@@ -1,8 +1,18 @@
 from __future__ import unicode_literals
 import unittest
 
+<<<<<<< HEAD
 from infi.clickhouse_orm.database import Database, DatabaseException, ServerError
 from infi.clickhouse_orm.models import Model, MergeModel, DistributedModel
+||||||| merged common ancestors
+from infi.clickhouse_orm.database import Database, DatabaseException
+from infi.clickhouse_orm.models import Model, MergeModel
+=======
+from infi.clickhouse_orm.system_models import SystemPart
+
+from infi.clickhouse_orm.database import Database, DatabaseException
+from infi.clickhouse_orm.models import Model, MergeModel
+>>>>>>> 7fb05896926acab163a1f373092bf22cc0f3cb4f
 from infi.clickhouse_orm.fields import *
 from infi.clickhouse_orm.engines import *
 
@@ -43,8 +53,12 @@ class EnginesTestCase(_EnginesHelperTestCase):
 
     def test_replicated_merge_tree(self):
         engine = MergeTree('date', ('date', 'event_id', 'event_group'), replica_table_path='/clickhouse/tables/{layer}-{shard}/hits', replica_name='{replica}')
-        expected = "ReplicatedMergeTree('/clickhouse/tables/{layer}-{shard}/hits', '{replica}', date, (date, event_id, event_group), 8192)"
+        # In ClickHouse 1.1.54310 custom partitioning key was introduced and new syntax is used
-        self.assertEquals(engine.create_table_sql(), expected)
+        if self.database.server_version >= (1, 1, 54310):
+            expected = "ReplicatedMergeTree('/clickhouse/tables/{layer}-{shard}/hits', '{replica}') PARTITION BY (toYYYYMM(`date`)) ORDER BY (date, event_id, event_group) SETTINGS index_granularity=8192"
+        else:
+            expected = "ReplicatedMergeTree('/clickhouse/tables/{layer}-{shard}/hits', '{replica}', date, (date, event_id, event_group), 8192)"
+        self.assertEquals(engine.create_table_sql(self.database), expected)
 
     def test_collapsing_merge_tree(self):
         class TestModel(SampleModel):
@@ -126,6 +140,17 @@ class EnginesTestCase(_EnginesHelperTestCase):
             'event_uversion': 2
         }, res[1].to_dict(include_readonly=True))
 
+    def test_custom_partitioning(self):
+        class TestModel(SampleModel):
+            engine = MergeTree(
+                order_by=('date', 'event_id', 'event_group'),
+                partition_key=('toYYYYMM(date)', 'event_group')
+            )
+        self._create_and_insert(TestModel)
+        parts = list(SystemPart.get(self.database))
+        self.assertEqual(1, len(parts))
+        self.assertEqual('(201701, 13)', parts[0].partition)
+
 
 class SampleModel(Model):
 

tests/test_inheritance.py

@@ -3,6 +3,7 @@ import unittest
 import datetime
 import pytz
 
+from infi.clickhouse_orm.database import Database
 from infi.clickhouse_orm.models import Model
 from infi.clickhouse_orm.fields import *
 from infi.clickhouse_orm.engines import *
@@ -19,9 +20,10 @@ class InheritanceTestCase(unittest.TestCase):
         self.assertFieldNames(Model2, ['date_field', 'int_field', 'float_field'])
 
     def test_create_table_sql(self):
-        sql1 = ParentModel.create_table_sql('default')
+        default_db = Database('default')
-        sql2 = Model1.create_table_sql('default')
+        sql1 = ParentModel.create_table_sql(default_db)
-        sql3 = Model2.create_table_sql('default')
+        sql2 = Model1.create_table_sql(default_db)
+        sql3 = Model2.create_table_sql(default_db)
         self.assertNotEqual(sql1, sql2)
         self.assertNotEqual(sql1, sql3)
         self.assertNotEqual(sql2, sql3)

tests/test_system_models.py

@@ -1,7 +1,10 @@
 from __future__ import unicode_literals
+
 import unittest
 from datetime import date
+
 import os
+
 from infi.clickhouse_orm.database import Database, DatabaseException
 from infi.clickhouse_orm.engines import *
 from infi.clickhouse_orm.fields import *
@@ -37,7 +40,9 @@ class SystemPartTest(unittest.TestCase):
     def setUp(self):
         self.database = Database('test-db')
         self.database.create_table(TestTable)
+        self.database.create_table(CustomPartitionedTable)
         self.database.insert([TestTable(date_field=date.today())])
+        self.database.insert([CustomPartitionedTable(date_field=date.today(), group_field=13)])
 
     def tearDown(self):
         self.database.drop_database()
@@ -51,40 +56,46 @@ class SystemPartTest(unittest.TestCase):
 
     def test_get_all(self):
         parts = SystemPart.get(self.database)
-        self.assertEqual(len(list(parts)), 1)
+        self.assertEqual(len(list(parts)), 2)
 
     def test_get_active(self):
         parts = list(SystemPart.get_active(self.database))
-        self.assertEqual(len(parts), 1)
+        self.assertEqual(len(parts), 2)
         parts[0].detach()
-        self.assertEqual(len(list(SystemPart.get_active(self.database))), 0)
+        self.assertEqual(len(list(SystemPart.get_active(self.database))), 1)
 
     def test_get_conditions(self):
         parts = list(SystemPart.get(self.database, conditions="table='testtable'"))
         self.assertEqual(len(parts), 1)
-        parts = list(SystemPart.get(self.database, conditions=u"table='othertable'"))
+        parts = list(SystemPart.get(self.database, conditions=u"table='custompartitionedtable'"))
+        self.assertEqual(len(parts), 1)
+        parts = list(SystemPart.get(self.database, conditions=u"table='invalidtable'"))
         self.assertEqual(len(parts), 0)
 
     def test_attach_detach(self):
         parts = list(SystemPart.get_active(self.database))
-        self.assertEqual(len(parts), 1)
+        self.assertEqual(len(parts), 2)
-        parts[0].detach()
+        for p in parts:
+            p.detach()
         self.assertEqual(len(list(SystemPart.get_active(self.database))), 0)
-        parts[0].attach()
+        for p in parts:
-        self.assertEqual(len(list(SystemPart.get_active(self.database))), 1)
+            p.attach()
+        self.assertEqual(len(list(SystemPart.get_active(self.database))), 2)
 
     def test_drop(self):
         parts = list(SystemPart.get_active(self.database))
-        parts[0].drop()
+        for p in parts:
+            p.drop()
         self.assertEqual(len(list(SystemPart.get_active(self.database))), 0)
 
     def test_freeze(self):
         parts = list(SystemPart.get(self.database))
         # There can be other backups in the folder
         prev_backups = set(self._get_backups())
-        parts[0].freeze()
+        for p in parts:
+            p.freeze()
         backups = set(self._get_backups())
-        self.assertEqual(len(backups), len(prev_backups) + 1)
+        self.assertEqual(len(backups), len(prev_backups) + 2)
 
     def test_fetch(self):
         # TODO Not tested, as I have no replication set
@@ -97,5 +108,12 @@ class TestTable(Model):
     engine = MergeTree('date_field', ('date_field',))
 
 
+class CustomPartitionedTable(Model):
+    date_field = DateField()
+    group_field = UInt32Field()
+
+    engine = MergeTree(order_by=('date_field', 'group_field'), partition_key=('toYYYYMM(date_field)', 'group_field'))
+
+
 class SystemTestModel(Model):
     system = True