class OCI8

def describe_table(table_name, table_only = false)
  if table_only
    # check my own tables only.
    __describe(table_name, OCI8::Metadata::Table, false)
  else
    # check tables, views, synonyms and public synonyms.
    # follow synonyms up to 20 times to prevent infinite loop
    # caused by recursive synonyms.
    recursive_level = 20
    recursive_level.times do
      metadata = __describe(table_name, OCI8::Metadata::Unknown, true)
      case metadata
      when OCI8::Metadata::Table, OCI8::Metadata::View
        return metadata
      when OCI8::Metadata::Synonym
        table_name = metadata.translated_name
        if metadata.obj_link and metadata.link.nil?
          # table_name is a synonym in a remote database for an object in the
          # remote database itself.
          table_name = "#{table_name}@#{metadata.obj_link}"
        end
      else
        raise OCIError.new(4043, table_name) # ORA-04043: object %s does not exist
      end
    end
    raise OCIError.new(36, recursive_level) # ORA-00036: maximum number of recursive SQL levels (%s) exceeded
  end
end