Rollback #5819 since it's compatible with PostgreSQL 8.1 only. References #5819.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4806 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

@@ -4,8 +4,6 @@
 
 * Pushing a record onto a has_many :through sets the association's foreign key to the associate's primary key and adds it to the correct association.  #5815, #5829 [josh@hasmanythrough.com]
 
-* PostgreSQL: simplify index introspection query.  #5819 [stephen_purcell@yahoo.com]
-
 * Add records to has_many :through using <<, push, and concat by creating the association record. Raise if base or associate are new records since both ids are required to create the association. #build raises since you can't associate an unsaved record. #create! takes an attributes hash and creates the associated record and its association in a transaction. [Jeremy Kemper]
 
     # Create a tagging to associate the post and tag.

activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

@@ -209,7 +209,11 @@ module ActiveRecord
              AND t.oid = d.indrelid
              AND t.relname = '#{table_name}'
              AND a.attrelid = t.oid
-             AND a.attnum = ANY (d.indkey)
+             AND ( d.indkey[0]=a.attnum OR d.indkey[1]=a.attnum
+                OR d.indkey[2]=a.attnum OR d.indkey[3]=a.attnum
+                OR d.indkey[4]=a.attnum OR d.indkey[5]=a.attnum
+                OR d.indkey[6]=a.attnum OR d.indkey[7]=a.attnum
+                OR d.indkey[8]=a.attnum OR d.indkey[9]=a.attnum )
           ORDER BY i.relname
         SQL