module Arel class Table include Arel::Crud include Arel::FactoryMethods @engine = nil class << self; attr_accessor :engine; end attr_accessor :name, :aliases, :table_alias # TableAlias and Table both have a #table_name which is the name of the underlying table alias :table_name :name def initialize(name, as: nil, type_caster: nil) @name = name.to_s @columns = nil @aliases = [] @type_caster = type_caster # Sometime AR sends an :as parameter to table, to let the table know # that it is an Alias. We may want to override new, and return a # TableAlias node? if as.to_s == @name as = nil end @table_alias = as end def alias name = "#{self.name}_2" Nodes::TableAlias.new(self, name).tap do |node| @aliases << node end end def from SelectManager.new(self) end def join relation, klass = Nodes::InnerJoin return from unless relation case relation when String, Nodes::SqlLiteral raise if relation.empty? klass = Nodes::StringJoin end from.join(relation, klass) end def outer_join relation join(relation, Nodes::OuterJoin) end def group *columns from.group(*columns) end def order *expr from.order(*expr) end def where condition from.where condition end def project *things from.project(*things) end def take amount from.take amount end def skip amount from.skip amount end def having expr from.having expr end def [] name ::Arel::Attribute.new self, name end def hash # Perf note: aliases and table alias is excluded from the hash # aliases can have a loop back to this table breaking hashes in parent # relations, for the vast majority of cases @name is unique to a query @name.hash end def eql? other self.class == other.class && self.name == other.name && self.aliases == other.aliases && self.table_alias == other.table_alias end alias :== :eql? def type_cast_for_database(attribute_name, value) type_caster.type_cast_for_database(attribute_name, value) end def able_to_type_cast? !type_caster.nil? end protected attr_reader :type_caster private def attributes_for columns return nil unless columns columns.map do |column| Attributes.for(column).new self, column.name.to_sym end end end end