--- a/server/migractions.py	Fri Aug 21 11:01:08 2015 +0200
+++ b/server/migractions.py	Tue Aug 25 11:11:34 2015 +0200
@@ -1085,8 +1085,9 @@
                                 default='n'):
                 raise SystemExit(1)
         self.cmd_add_relation_type(newname, commit=True)
-        self.rqlexec('SET X %s Y WHERE X %s Y' % (newname, oldname),
-                     ask_confirm=self.verbosity>=2)
+        if not self.repo.schema[oldname].rule:
+            self.rqlexec('SET X %s Y WHERE X %s Y' % (newname, oldname),
+                         ask_confirm=self.verbosity>=2)
         self.cmd_drop_relation_type(oldname, commit=commit)
 
     def cmd_add_relation_definition(self, subjtype, rtype, objtype, commit=True):

--- a/server/test/datacomputed/migratedapp/schema.py	Fri Aug 21 11:01:08 2015 +0200
+++ b/server/test/datacomputed/migratedapp/schema.py	Tue Aug 25 11:11:34 2015 +0200
@@ -55,3 +55,7 @@
 
 class whatever(ComputedRelation):
     rule = 'S employees E, O associates E'
+
+
+class renamed(ComputedRelation):
+    rule = 'S employees E, O concerns E'

--- a/server/test/datacomputed/schema.py	Fri Aug 21 11:01:08 2015 +0200
+++ b/server/test/datacomputed/schema.py	Tue Aug 25 11:11:34 2015 +0200
@@ -52,3 +52,7 @@
 
 class whatever(ComputedRelation):
     rule = 'S employees E, O concerns E'
+
+
+class to_be_renamed(ComputedRelation):
+    rule = 'S employees E, O concerns E'

--- a/server/test/unittest_migractions.py	Fri Aug 21 11:01:08 2015 +0200
+++ b/server/test/unittest_migractions.py	Tue Aug 25 11:11:34 2015 +0200
@@ -763,6 +763,12 @@
                          'Cannot synchronize a relation definition for a computed '
                          'relation (whatever)')
 
+    def test_computed_relation_rename_relation_type(self):
+        with self.mh() as (cnx, mh):
+            mh.cmd_rename_relation_type('to_be_renamed', 'renamed')
+        self.assertIn('renamed', self.schema)
+        self.assertNotIn('to_be_renamed', self.schema)
+
     # computed attributes migration ############################################
 
     def setup_add_score(self):