prepare_statement

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 1198
        def prepare_statement(sql)
          sql_key = sql_key(sql)
          unless @statements.key? sql_key
            nextkey = @statements.next_key
            @connection.prepare nextkey, sql
            @statements[sql_key] = nextkey
          end
          @statements[sql_key]
        end