tables_in_string

# File activerecord/lib/active_record/relation.rb, line 482
    def tables_in_string(string)
      return [] if string.blank?
      # always convert table names to downcase as in Oracle quoted table names are in uppercase
      # ignore raw_sql_ that is used by Oracle adapter as alias for limit/offset subqueries
      string.scan(/([a-zA-Z_][.\w]+).?\./).flatten.map{ |s| s.downcase }.uniq - ['raw_sql_']
    end