serious overhaul to get eager loads to work inline with an inheriting mapper, when the inheritance/eager loads share the same table. mapper inheritance will also favor the columns from the child table over those of the parent table when assigning column values to object attributes. "correlated subqueries" require a flag "correlated=True" if they are in the FROM clause of another SELECT statement, and they want to be correlated. this flag is set by default when using an "exists" clause.

1 files changed, 18 insertions, 5 deletions

diff --git a/lib/sqlalchemy/mapping/mapper.py b/lib/sqlalchemy/mapping/mapper.py
index 330c75c31..93af9d7f2 100644
--- a/lib/sqlalchemy/mapping/mapper.py
+++ b/lib/sqlalchemy/mapping/mapper.py
@@ -145,7 +145,12 @@ class Mapper(object):
                 prop = ColumnProperty(column)
                 self.props[column.key] = prop
             elif isinstance(prop, ColumnProperty):
-                prop.columns.append(column)
+                # the order which columns are appended to a ColumnProperty is significant, as the 
+                # column at index 0 determines which result column is used to populate the object
+                # attribute, in the case of mapping against a join with column names repeated
+                # (and particularly in an inheritance relationship)
+                prop.columns.insert(0, column)
+                #prop.columns.append(column)
             else:
                 if not allow_column_override:
                     raise ArgumentError("WARNING: column '%s' not being added due to property '%s'.  Specify 'allow_column_override=True' to mapper() to ignore this condition." % (column.key, repr(prop)))
@@ -179,6 +184,12 @@ class Mapper(object):
             if getattr(prop, 'key', None) is None:
                 prop.init(key, self)
 
+        # this prints a summary of the object attributes and how they
+        # will be mapped to table columns
+        #print "mapper %s, columntoproperty:" % (self.class_.__name__)
+        #for key, value in self.columntoproperty.iteritems():
+        #    print key.table.name, key.key, [(v.key, v) for v in value]
+            
     engines = property(lambda s: [t.engine for t in s.tables])
 
     def add_property(self, key, prop):
@@ -638,9 +649,7 @@ class Mapper(object):
     def delete_obj(self, objects, uow):
         """called by a UnitOfWork object to delete objects, which involves a
         DELETE statement for each table used by this mapper, for each object in the list."""
-        l = list(self.tables)
-        l.reverse()
-        for table in l:
+        for table in util.reversed(self.tables):
             if not self._has_pks(table):
                 continue
             delete = []
@@ -703,7 +712,8 @@ class Mapper(object):
                 order_by = self.table.default_order_by()
 
         if self._should_nest(**kwargs):
-            s2 = sql.select(self.table.primary_key, whereclause, use_labels=True, **kwargs)
+            s2 = sql.select(self.table.primary_key, whereclause, use_labels=True, from_obj=[self.table], **kwargs)
+#            raise "ok first thing", str(s2)
             if not kwargs.get('distinct', False) and order_by:
                 s2.order_by(*util.to_list(order_by))
             s3 = s2.alias('rowcount')
@@ -711,6 +721,7 @@ class Mapper(object):
             for i in range(0, len(self.table.primary_key)):
                 crit.append(s3.primary_key[i] == self.table.primary_key[i])
             statement = sql.select([], sql.and_(*crit), from_obj=[self.table], use_labels=True)
+ #           raise "OK statement", str(statement)
             if order_by:
                 statement.order_by(*util.to_list(order_by))
         else:
@@ -930,6 +941,8 @@ class TableFinder(sql.ClauseVisitor):
         table.accept_visitor(self)
     def visit_table(self, table):
         self.tables.append(table)
+    def __len__(self):
+        return len(self.tables)
     def __getitem__(self, i):
         return self.tables[i]
     def __iter__(self):