class ActiveRecord::QueryMethods::WhereChain - activerecord-4.2.4 Documentation

# class ActiveRecord::QueryMethods::WhereChain

WhereChain objects act as placeholder for queries in which where does not have any parameter. In this case, where must be chained with not to return a new relation.

### Public Class Methods

new(scope) click to toggle source

    # File lib/active_record/relation/query_methods.rb, line 14
    def initialize(scope)
      @scope = scope
    end

### Public Instance Methods

not(opts, *rest) click to toggle source

Returns a new relation expressing WHERE + NOT condition according to the conditions in the arguments.

`not` accepts conditions as a string, array, or hash. See where for more details on each format.

    User.where.not("name = 'Jon'")
    # SELECT * FROM users WHERE NOT (name = 'Jon')

    User.where.not(["name = ?", "Jon"])
    # SELECT * FROM users WHERE NOT (name = 'Jon')

    User.where.not(name: "Jon")
    # SELECT * FROM users WHERE name != 'Jon'

    User.where.not(name: nil)
    # SELECT * FROM users WHERE name IS NOT NULL

    User.where.not(name: %w(Ko1 Nobu))
    # SELECT * FROM users WHERE name NOT IN ('Ko1', 'Nobu')

    User.where.not(name: "Jon", role: "admin")
    # SELECT * FROM users WHERE name != 'Jon' AND role != 'admin'

    # File lib/active_record/relation/query_methods.rb, line 41
    def not(opts, *rest)
      where_value = @scope.send(:build_where, opts, rest).map do |rel|
        case rel
        when NilClass
          raise ArgumentError, 'Invalid argument for .where.not(), got nil.'
        when Arel::Nodes::In
          Arel::Nodes::NotIn.new(rel.left, rel.right)
        when Arel::Nodes::Equality
          Arel::Nodes::NotEqual.new(rel.left, rel.right)
        when String
          Arel::Nodes::Not.new(Arel::Nodes::SqlLiteral.new(rel))
        else
          Arel::Nodes::Not.new(rel)
        end
      end

      @scope.references!(PredicateBuilder.references(opts)) if Hash === opts
      @scope.where_values += where_value
      @scope
    end