diff options
Diffstat (limited to 'lib/sqlalchemy/sql/expression.py')
| -rw-r--r-- | lib/sqlalchemy/sql/expression.py | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py index 6dc134d98..f0c6134e5 100644 --- a/lib/sqlalchemy/sql/expression.py +++ b/lib/sqlalchemy/sql/expression.py @@ -795,7 +795,7 @@ def intersect_all(*selects, **kwargs): return CompoundSelect(CompoundSelect.INTERSECT_ALL, *selects, **kwargs) -def alias(selectable, name=None): +def alias(selectable, name=None, flat=False): """Return an :class:`.Alias` object. An :class:`.Alias` represents any :class:`.FromClause` @@ -2636,7 +2636,7 @@ class FromClause(Selectable): return Join(self, right, onclause, True) - def alias(self, name=None): + def alias(self, name=None, flat=False): """return an alias of this :class:`.FromClause`. This is shorthand for calling:: @@ -3980,7 +3980,7 @@ class Join(FromClause): def bind(self): return self.left.bind or self.right.bind - def alias(self, name=None): + def alias(self, name=None, flat=False): """return an alias of this :class:`.Join`. Used against a :class:`.Join` object, @@ -4008,7 +4008,17 @@ class Join(FromClause): aliases. """ - return self.select(use_labels=True, correlate=False).alias(name) + if flat: + assert name is None, "Can't send name argument with flat" + left_a, right_a = self.left.alias(flat=True), \ + self.right.alias(flat=True) + adapter = sqlutil.ClauseAdapter(left_a).\ + chain(sqlutil.ClauseAdapter(right_a)) + + return left_a.join(right_a, + adapter.traverse(self.onclause), isouter=self.isouter) + else: + return self.select(use_labels=True, correlate=False).alias(name) @property def _hide_froms(self): @@ -4138,7 +4148,7 @@ class CTE(Alias): self._restates = _restates super(CTE, self).__init__(selectable, name=name) - def alias(self, name=None): + def alias(self, name=None, flat=False): return CTE( self.original, name=name, @@ -4221,10 +4231,10 @@ class FromGrouping(FromClause): @property def foreign_keys(self): - # this could be - # self.element.foreign_keys - # see SelectableTest.test_join_condition - return set() + return self.element.foreign_keys + + def is_derived_from(self, element): + return self.element.is_derived_from(element) @property def _hide_froms(self): |