added 'remote_side' functionality to lazy clause generation

1 files changed, 9 insertions, 5 deletions

diff --git a/lib/sqlalchemy/orm/strategies.py b/lib/sqlalchemy/orm/strategies.py
index 28fbdcfd3..a3a92841d 100644
--- a/lib/sqlalchemy/orm/strategies.py
+++ b/lib/sqlalchemy/orm/strategies.py
@@ -129,7 +129,8 @@ class AbstractRelationLoader(LoaderStrategy):
         self.cascade = self.parent_property.cascade
         self.attributeext = self.parent_property.attributeext
         self.order_by = self.parent_property.order_by
-
+        self.remote_side = self.parent_property.remote_side
+        
     def _init_instance_attribute(self, instance, callable_=None):
         return sessionlib.attribute_manager.init_instance_attribute(instance, self.key, self.uselist, cascade=self.cascade,  trackparent=True, callable_=callable_)
         
@@ -151,7 +152,7 @@ NoLoader.logger = logging.class_logger(NoLoader)
 class LazyLoader(AbstractRelationLoader):
     def init(self):
         super(LazyLoader, self).init()
-        (self.lazywhere, self.lazybinds, self.lazyreverse) = self._create_lazy_clause(self.parent.unjoined_table, self.primaryjoin, self.secondaryjoin, self.foreignkey)
+        (self.lazywhere, self.lazybinds, self.lazyreverse) = self._create_lazy_clause(self.parent.unjoined_table, self.primaryjoin, self.secondaryjoin, self.foreignkey, self.remote_side)
         # determine if our "lazywhere" clause is the same as the mapper's
         # get() clause.  then we can just use mapper.get()
         self.use_get = not self.uselist and query.Query(self.mapper)._get_clause.compare(self.lazywhere)
@@ -235,12 +236,15 @@ class LazyLoader(AbstractRelationLoader):
                 # to load data into it.
                 sessionlib.attribute_manager.reset_instance_attribute(instance, self.key)
 
-    def _create_lazy_clause(self, table, primaryjoin, secondaryjoin, foreignkey):
+    def _create_lazy_clause(self, table, primaryjoin, secondaryjoin, foreignkey, remote_side):
         binds = {}
         reverse = {}
         def column_in_table(table, column):
             return table.corresponding_column(column, raiseerr=False, keys_ok=False) is not None
 
+        if remote_side is None or len(remote_side) == 0:
+            remote_side = foreignkey
+            
         def find_column_in_expr(expr):
             if not isinstance(expr, sql.ColumnElement):
                 return None
@@ -259,13 +263,13 @@ class LazyLoader(AbstractRelationLoader):
             if leftcol is None or rightcol is None:
                 return
             circular = leftcol.table is rightcol.table
-            if ((not circular and column_in_table(table, leftcol)) or (circular and rightcol in foreignkey)):
+            if ((not circular and column_in_table(table, leftcol)) or (circular and rightcol in remote_side)):
                 col = leftcol
                 binary.left = binds.setdefault(leftcol,
                         sql.bindparam(bind_label(), None, shortname=leftcol.name, type=binary.right.type))
                 reverse[rightcol] = binds[col]
 
-            if (leftcol is not rightcol) and ((not circular and column_in_table(table, rightcol)) or (circular and leftcol in foreignkey)):
+            if (leftcol is not rightcol) and ((not circular and column_in_table(table, rightcol)) or (circular and leftcol in remote_side)):
                 col = rightcol
                 binary.right = binds.setdefault(rightcol,
                         sql.bindparam(bind_label(), None, shortname=rightcol.name, type=binary.left.type))