sequence_name_from_parts

# File activerecord/lib/active_record/connection_adapters/postgresql/column.rb, line 27
        def sequence_name_from_parts(table_name, column_name, suffix)
          over_length = [table_name, column_name, suffix].map(&:length).sum + 2 - max_identifier_length

          if over_length > 0
            column_name_length = [(max_identifier_length - suffix.length - 2) / 2, column_name.length].min
            over_length -= column_name.length - column_name_length
            column_name = column_name[0, column_name_length - [over_length, 0].min]
          end

          if over_length > 0
            table_name = table_name[0, table_name.length - over_length]
          end

          "#{table_name}_#{column_name}_#{suffix}"
        end