def update(id, attributes)
      set_attrs, *bind_values = update_attributes(attributes)
      [
        [
          "UPDATE #{@index_name} SET",
          set_attrs,
          "WHERE id = ?"
        ].join(" "),
        *bind_values.push(id)
      ]
    end
def update(id, attributes)
      set_attrs, *bind_values = update_attributes(attributes)
      [
        [
          "UPDATE #{@index_name} SET",
          set_attrs,
          "WHERE id = ?"
        ].join(" "),
        *bind_values.push(id)
      ]
    end
Build a SphinxQL query to update the record identified by +id+ with the given attributes.

 @param [Fixnum] id
   the unique ID of the document to update

 @param [Hash] attributes
   a Hash of attributes

 @return [String]
   the SphinxQL to update the record