Merge pull request #79 from sdrenn/final-clause

final clause

clickhouse_sqlalchemy/drivers/base.py

@@ -257,6 +257,11 @@ def _compose_select_body(
         if sample_clause is not None:
             text += self.sample_clause(select, **kwargs)
 
+        final_clause = getattr(select, '_final_clause', None)
+
+        if final_clause is not None:
+            text += self.final_clause()
+
         if select._whereclause is not None:
             t = select._whereclause._compiler_dispatch(self, **kwargs)
             if t:
@@ -285,6 +290,9 @@ def _compose_select_body(
     def sample_clause(self, select, **kw):
         return " \nSAMPLE " + self.process(select._sample_clause, **kw)
 
+    def final_clause(self):
+        return " \nFINAL"
+
     def group_by_clause(self, select, **kw):
         text = ""
 

clickhouse_sqlalchemy/orm/query.py

@@ -13,6 +13,7 @@
 
 class Query(BaseQuery):
     _with_totals = False
+    _final = None
     _sample = None
     _array_join = None
 
@@ -21,6 +22,7 @@ def _compile_context(self, labels=True):
         statement = context.statement
 
         statement._with_totals = self._with_totals
+        statement._final_clause = self._final
         statement._sample_clause = sample_clause(self._sample)
         statement._array_join = self._array_join
 
@@ -41,6 +43,11 @@ def array_join(self, *columns):
         self._array_join = ArrayJoin(*columns)
         return self
 
+    def final(self):
+        self._final = True
+
+        return self
+
     def sample(self, sample):
         self._sample = sample
 

clickhouse_sqlalchemy/sql/selectable.py

@@ -28,13 +28,18 @@ def __init__(self, left, right,
 
 class Select(StandardSelect):
     _with_totals = False
+    _final_clause = None
     _sample_clause = None
     _array_join = None
 
     def with_totals(self):
         self._with_totals = True
         return self
 
+    def final(self):
+        self._final_clause = True
+        return self
+
     def sample(self, sample):
         self._sample_clause = sample_clause(sample)
         return self

tests/orm/test_select.py

@@ -105,6 +105,15 @@ def test_sample(self):
             'SELECT x AS t1_x FROM t1 SAMPLE 0.1 GROUP BY x'
         )
 
+    def test_final(self):
+        table = self.create_table()
+
+        query = session.query(table.c.x).final().group_by(table.c.x)
+        self.assertEqual(
+            self.compile(query),
+            'SELECT x AS t1_x FROM t1 FINAL GROUP BY x'
+        )
+
     def test_lambda_functions(self):
         query = self.session.query(
             func.arrayFilter(

tests/sql/test_selectable.py

@@ -46,6 +46,15 @@ def test_sample(self):
             'SELECT x FROM t1 SAMPLE 0.1 GROUP BY x'
         )
 
+    def test_final(self):
+        table = self.create_table()
+
+        query = select([table.c.x]).final().group_by(table.c.x)
+        self.assertEqual(
+            self.compile(query),
+            'SELECT x FROM t1 FINAL GROUP BY x'
+        )
+
     def test_nested_type(self):
         table = self.create_table(
             't1',