Added documentation for PostGreSQL database_statements [ci skip]

 - Added documentation for index_name_exists? and rename_index.
 - Also changed rails to \Rails in documentation of
   allowed_index_name_length.

1 files changed, 3 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
index 168180cfd3..70fc1a6bd8 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
@@ -100,6 +100,7 @@ module ActiveRecord
           SQL
         end
 
+        # Verifies existence of an index with a given name.
         def index_name_exists?(table_name, index_name, default)
           exec_query(<<-SQL, 'SCHEMA').rows.first[0].to_i > 0
             SELECT COUNT(*)
@@ -462,6 +463,8 @@ module ActiveRecord
           execute "DROP INDEX #{quote_table_name(index_name)}"
         end
 
+        # Renames an index of a table. Raises error if length of new
+        # index name is greater than allowed limit.
         def rename_index(table_name, old_name, new_name)
           validate_index_length!(table_name, new_name)