Index: openacs-4/packages/acs-kernel/sql/postgresql/acs-relationships-create.sql
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-kernel/sql/postgresql/acs-relationships-create.sql,v
diff -u -r1.28 -r1.29
--- openacs-4/packages/acs-kernel/sql/postgresql/acs-relationships-create.sql	4 Jan 2010 19:54:37 -0000	1.28
+++ openacs-4/packages/acs-kernel/sql/postgresql/acs-relationships-create.sql	5 Jan 2010 15:30:26 -0000	1.29
@@ -378,15 +378,17 @@
                         constraint acs_data_links_obj_two_fk
                         references acs_objects (object_id)
                         on delete cascade,
-        relation_tag    varchar(100),
-        constraint acs_data_links_un unique
-        (object_id_one, object_id_two, relation_tag)
+        relation_tag    varchar(100)
 );
 
 create index acs_data_links_id_one_idx on acs_data_links (object_id_one);
 create index acs_data_links_id_two_idx on acs_data_links (object_id_two);
 create index acs_data_links_rel_tag_idx on acs_data_links (relation_tag);
 
+create unique index acs_data_links_un on acs_data_links (
+  object_id_one, object_id_two, relation_tag
+);
+
 --------------
 -- TRIGGERS --
 --------------
