1 files changed, 11 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index e77ae93c21..224c007f3c 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -250,6 +250,11 @@ module ActiveRecord
         true
       end
 
+      # Does PostgreSQL support finding primary key on non-ActiveRecord tables?
+      def supports_primary_key? #:nodoc:
+        true
+      end
+
       # Does PostgreSQL support standard conforming strings?
       def supports_standard_conforming_strings?
         # Temporarily set the client message level above error to prevent unintentional
@@ -811,6 +816,12 @@ module ActiveRecord
         nil
       end
 
+      # Returns just a table's primary key
+      def primary_key(table)
+        pk_and_sequence = pk_and_sequence_for(table)
+        pk_and_sequence && pk_and_sequence.first
+      end
+
       # Renames a table.
       def rename_table(name, new_name)
         execute "ALTER TABLE #{quote_table_name(name)} RENAME TO #{quote_table_name(new_name)}"