- fixed bug introduced in r4070 where union() and other compound selects would not get

an OID column if it only contained one selectable element, due to missing return in _proxy_column()
- visit_column() calls itself to render a primary key col being used as the interpretation of the oid col instead of relying upon broken partial logic

2 files changed, 2 insertions, 3 deletions

diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py
index 02f6efce1..e87d3d2fb 100644
--- a/lib/sqlalchemy/sql/compiler.py
+++ b/lib/sqlalchemy/sql/compiler.py
@@ -269,8 +269,7 @@ class DefaultCompiler(engine.Compiled):
                     return schema_prefix + self.preparer.quote(column.table, ANONYMOUS_LABEL.sub(self._process_anon, column.table.name)) + "." + n
             elif len(column.table.primary_key) != 0:
                 pk = list(column.table.primary_key)[0]
-                pkname = (pk.is_literal and name or self._truncated_identifier("colident", pk.name))
-                return schema_prefix + self.preparer.quote(column.table, ANONYMOUS_LABEL.sub(self._process_anon, column.table.name)) + "." + self.preparer.quote(pk, pkname)
+                return self.visit_column(pk, result_map=result_map, use_schema=use_schema, **kwargs)
             else:
                 return None
         elif column.table is None or not column.table.named_with_column:
diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py
index 79eb1759d..0b7684803 100644
--- a/lib/sqlalchemy/sql/expression.py
+++ b/lib/sqlalchemy/sql/expression.py
@@ -2935,7 +2935,6 @@ class CompoundSelect(_SelectBaseMixin, FromClause):
             if s.oid_column:
                 self.oid_column = self._proxy_column(s.oid_column)
 
-
     def self_group(self, against=None):
         return _FromGrouping(self)
 
@@ -2956,6 +2955,7 @@ class CompoundSelect(_SelectBaseMixin, FromClause):
             else:
                 col = column._make_proxy(self)
             col_ordering.append(col)
+            return col
         else:
             col_ordering.append(column)
             existing = self._col_map[self.selects[0]][len(col_ordering) - 1]