Merge pull request piccolo-orm#149 from aminalaee/add-distinct-method-docs

add distinct method docs

Author: dantownsend

docs/src/piccolo/query_clauses/distinct.rst

@@ -0,0 +1,15 @@
+.. _distinct:
+
+distinct
+========
+
+You can use ``distinct`` clauses with the following queries:
+
+* :ref:`Select`
+
+.. code-block:: python
+
+    >>> Band.select(Band.name).distinct().run_sync()
+    [{'title': 'Pythonistas'}]
+
+This is equivalent to ``SELECT DISTINCT name FROM band`` in SQL.

docs/src/piccolo/query_types/select.rst

@@ -172,7 +172,7 @@ Query clauses
 -------------
 
 batch
-~~~~~~~
+~~~~~
 
 See :ref:`batch`.
 
@@ -228,6 +228,11 @@ offset
 
 See  :ref:`offset`.
 
+distinct
+~~~~~~~~
+
+See  :ref:`distinct`.
+
 order_by
 ~~~~~~~~