Arel::Expression

   # File lib/arel/algebra/expression.rb, line 6
6:     def initialize(attribute, aliaz = nil, ancestor = nil)
7:       super(attribute.relation, aliaz, :alias => aliaz, :ancestor => ancestor)
8:       @attribute = attribute
9:     end

    # File lib/arel/algebra/expression.rb, line 11
11:     def aggregation?
12:       true
13:     end

    # File lib/arel/algebra/expression.rb, line 19
19:     def as(aliaz)
20:       self.class.new(attribute, aliaz, self)
21:     end

    # File lib/arel/algebra/expression.rb, line 23
23:     def bind(new_relation)
24:       new_relation == relation ? self : self.class.new(attribute.bind(new_relation), @alias, self)
25:     end

    # File lib/arel/algebra/expression.rb, line 27
27:     def to_attribute(relation)
28:       Attribute.new(relation, @alias, :ancestor => self)
29:     end

    # File lib/arel/algebra/expression.rb, line 15
15:     def to_sql(formatter = Sql::SelectClause.new(relation))
16:       formatter.expression self
17:     end