method

add_order_by_for_association_limiting!

Ruby on Rails latest stable (v6.1.7.7) - 0 notes - Class: ActiveRecord::ConnectionAdapters::PostgreSQLAdapter

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Method deprecated or moved

This method is deprecated or moved on the latest stable version. The last existing version (v2.3.8) is shown here.

add_order_by_for_association_limiting!(sql, options) public

Returns an ORDER BY clause for the passed order option.

PostgreSQL does not allow arbitrary ordering when using DISTINCT ON, so we work around this by wrapping the sql string as a sub-select and ordering in that query.

Show source

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 914
      def add_order_by_for_association_limiting!(sql, options) #:nodoc:
        return sql if options[:order].blank?

        order = options[:order].split(',').collect { |s| s.strip }.reject(&:blank?)
        order.map! { |s| 'DESC' if s =~ /\bdesc$/i }
        order = order.zip((0...order.size).to_a).map { |s,i| "id_list.alias_#{i} #{s}" }.join(', ')

        sql.replace "SELECT * FROM (#{sql}) AS id_list ORDER BY #{order}"
      end

add_order_by_for_association_limiting!

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Method deprecated or moved

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