- Fixed bug in new :class:`.TextAsFrom` construct where :class:`.Column`-

oriented row lookups were not matching up to the ad-hoc :class:`.ColumnClause`
objects that :class:`.TextAsFrom` generates, thereby making it not
usable as a target in :meth:`.Query.from_statement`.  Also fixed
:meth:`.Query.from_statement` mechanics to not mistake a :class:`.TextAsFrom`
for a :class:`.Select` construct.  This bug is also an 0.9 regression
as the :meth:`.Text.columns` method is called to accommodate the
:paramref:`.text.typemap` argument. [ticket:2932]

3 files changed, 12 insertions, 2 deletions

diff --git a/lib/sqlalchemy/orm/query.py b/lib/sqlalchemy/orm/query.py
index 10d635b8d..949c7eff9 100644
--- a/lib/sqlalchemy/orm/query.py
+++ b/lib/sqlalchemy/orm/query.py
@@ -3471,6 +3471,7 @@ class QueryContext(object):
 
         if query._statement is not None:
             if isinstance(query._statement, expression.SelectBase) and \
+                                not query._statement._textual and \
                                 not query._statement.use_labels:
                 self.statement = query._statement.apply_labels()
             else:
diff --git a/lib/sqlalchemy/sql/elements.py b/lib/sqlalchemy/sql/elements.py
index 975cf2d79..cca03851f 100644
--- a/lib/sqlalchemy/sql/elements.py
+++ b/lib/sqlalchemy/sql/elements.py
@@ -2920,9 +2920,12 @@ class ColumnClause(Immutable, ColumnElement):
 
     def _compare_name_for_result(self, other):
         if self.is_literal or \
-            self.table is None or \
+            self.table is None or self.table._textual or \
             not hasattr(other, 'proxy_set') or (
-            isinstance(other, ColumnClause) and other.is_literal
+            isinstance(other, ColumnClause) and
+                (other.is_literal or
+                        other.table is None or
+                        other.table._textual)
         ):
             return super(ColumnClause, self).\
                     _compare_name_for_result(other)
diff --git a/lib/sqlalchemy/sql/selectable.py b/lib/sqlalchemy/sql/selectable.py
index 01d617259..bda3d655e 100644
--- a/lib/sqlalchemy/sql/selectable.py
+++ b/lib/sqlalchemy/sql/selectable.py
@@ -137,6 +137,10 @@ class FromClause(Selectable):
     named_with_column = False
     _hide_froms = []
 
+    _textual = False
+    """a marker that allows us to easily distinguish a :class:`.TextAsFrom`
+    or similar object from other kinds of :class:`.FromClause` objects."""
+
     schema = None
     """Define the 'schema' attribute for this :class:`.FromClause`.
 
@@ -3046,6 +3050,8 @@ class TextAsFrom(SelectBase):
     """
     __visit_name__ = "text_as_from"
 
+    _textual = True
+
     def __init__(self, text, columns):
         self.element = text
         self.column_args = columns