id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
19080	"ChangeList.get_queryset() automatically applies select_related() in a very ""brute"" way"	Béres Botond	Tomek Paczkowski	"If there is a '''single''' related field from the listing model in `list_display`, `ChangeList.get_queryset` will apply `select_related()` so it will join everything, with no depth or field limitations.

Combined with the fact that there's no documented way to clear that (#16856), it's quite undesirable behaviour. 

In my opinion this could be resolved in 2 ways:
1. Remove that .select_related() call altogether and let the developer choose the exact optimization if he is displaying related fields in the listing
2. Optimize the select_related() call so that it's constructed exactly based on which fields appear in `list_display`"	Cleanup/optimization	closed	contrib.admin	1.4	Normal	fixed	performance	tomek@…	Accepted	1	0	0	0	0	0