Small improvement to docs/model-api.txt

        row = cursor.fetchone()

        return row

Note that ``db`` and ``cursor`` simply use the standard `Python DB-API`_.

If your custom SQL statement alters the data in your database -- for example,

via a ``DELETE``, ``INSERT`` or ``UPDATE`` -- you'll need to call

``db.commit()``. example::

If you're not familiar with the Python DB-API, note that the SQL statement in

    def my_custom_sql2(self):

        cursor = db.cursor()

        cursor.execute("DELETE FROM bar WHERE baz = %s", [self.baz])

        db.commit()

``db`` and ``cursor`` simply use the standard `Python DB-API`_. If you're not

familiar with the Python DB-API, note that the SQL statement in

``cursor.execute()`` uses placeholders, ``"%s"``, rather than adding parameters

directly within the SQL. If you use this technique, the underlying database

library will automatically add quotes and escaping to your parameter(s) as