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
35015	Update MySQL migration documentation for Mysql 8	Nicolas Lupien	nobody	"Now that Django dropped support for MySQL 5.7, I think the documentation is no longer valid. 

> MySQL lacks support for transactions around schema alteration operations, meaning that if a migration fails to apply you will have to manually unpick the changes in order to try again (it’s impossible to roll back to an earlier point).
> 
> In addition, MySQL will fully rewrite tables for almost every schema operation and generally takes a time proportional to the number of rows in the table to add or remove columns. On slower hardware this can be worse than a minute per million rows - adding a few columns to a table with just a few million rows could lock your site up for over ten minutes.
> 
> Finally, MySQL has relatively small limits on name lengths for columns, tables and indexes, as well as a limit on the combined size of all columns an index covers. This means that indexes that are possible on other backends will fail to be created under MySQL.

https://docs.djangoproject.com/en/5.0/topics/migrations/#mysql"	Uncategorized	new	Documentation	5.0	Normal				Unreviewed	0	0	0	0	0	0