# File lib/arel/table.rb, line 32 def primary_key if $VERBOSE warn "primary_key (\#{caller.first}) is deprecated and will be removed in ARel 4.0.0\n" end @primary_key ||= begin primary_key_name = @engine.connection.primary_key(name) # some tables might be without primary key primary_key_name && self[primary_key_name] end end