- added concept of 'require_embedded' to corresponding_column.

requires that the target column be present in a sub-element of the
target selectable.
- embedded logic above more appropriate for ClauseAdapter functionality
since its trying to "pull up" clauses that represent columns within
a larger union up to the level of the union itself.
- the "direction" test against the "foreign_keys" collection apparently
works for an exact "column 'x' is present in the collection", no proxy
relationships needed.  fixes the case of relating a selectable/alias
to one of its underlying tables, probably fixes other scenarios

1 files changed, 2 insertions, 2 deletions

diff --git a/lib/sqlalchemy/ansisql.py b/lib/sqlalchemy/ansisql.py
index 19cde3862..5d5c42208 100644
--- a/lib/sqlalchemy/ansisql.py
+++ b/lib/sqlalchemy/ansisql.py
@@ -391,9 +391,9 @@ class ANSICompiler(sql.Compiled):
                 c.accept_visitor(self)
                 inner_columns[self.get_str(c)] = c
                 continue
-            try:
+            if hasattr(c, '_selectable'):
                 s = c._selectable()
-            except AttributeError:
+            else:
                 c.accept_visitor(self)
                 inner_columns[self.get_str(c)] = c
                 continue