method

subquery_for

v4.0.2 - Show latest stable - Class: ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter

subquery_for(key, select)

protected

MySQL is too stupid to create a temporary table for use subquery, so we have to give it some prompting in the form of a subsubquery. Ugh!

# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 620
      def subquery_for(key, select)
        subsubselect = select.clone
        subsubselect.projections = [key]

        subselect = Arel::SelectManager.new(select.engine)
        subselect.project Arel.sql(key.name)
        subselect.from subsubselect.as('__active_record_temp')
      end

subquery_for

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