--- a/server/msplanner.py	Fri Jul 31 14:18:53 2009 +0200
+++ b/server/msplanner.py	Tue Aug 04 18:48:46 2009 +0200
@@ -100,6 +100,16 @@
 AbstractSource.dont_cross_relations = ()
 AbstractSource.cross_relations = ()
 
+def need_source_access_relation(vargraph):
+    if not vargraph:
+        return False
+    # check vargraph contains some other relation than the identity relation
+    # test of key nature since it may be a variable name (don't care about that)
+    # or a 2-uple (var1, var2) associated to the relation to traverse to go from
+    # var1 to var2
+    return any(key for key, val in vargraph.iteritems()
+               if isinstance(key, tuple) and val != 'identity')
+
 def need_aggr_step(select, sources, stepdefs=None):
     """return True if a temporary table is necessary to store some partial
     results to execute the given query
@@ -559,7 +569,8 @@
             # testing for rqlst with nothing in vargraph nor defined_vars is the
             # simplest way the check the condition explained below
             if not self.system_source in self._sourcesterms and \
-                   not self.rqlst.vargraph and not self.rqlst.defined_vars:
+                   not self.rqlst.defined_vars and \
+                   not need_source_access_relation(self.rqlst.vargraph):
                 self._sourcesterms = {self.system_source: {}}
         elif not self.needsplit:
             if not allequals(self._sourcesterms.itervalues()):

--- a/server/test/unittest_msplanner.py	Fri Jul 31 14:18:53 2009 +0200
+++ b/server/test/unittest_msplanner.py	Tue Aug 04 18:48:46 2009 +0200
@@ -1957,6 +1957,12 @@
                      None, None, [self.system], {}, [])],
                    {'x': 999998, 'u': 999999})
 
+    def test_nonregr_identity_no_source_access(self):
+        repo._type_source_cache[999999] = ('CWUser', 'ldap', 999998)
+        self._test('Any S WHERE S identity U, S eid %(s)s, U eid %(u)s',
+                   [('OneFetchStep', [('Any 999999 WHERE 999999 identity 999999', [{}])],
+                     None, None, [self.system], {}, [])],
+                   {'s': 999999, 'u': 999999})
 
 class MSPlannerTwoSameExternalSourcesTC(BasePlannerTC):
     """test planner related feature on a 3-sources repository: