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
21761	"Confused about ""Forced update did not affect any rows."""	jeroen.pulles@…	nobody	"I have a ''DatabaseError(""Forced update did not affect any rows."")'' (from model.save_base).

I cannot reproduce the error; Manually running save(force_update) on not-really-changed objects of the same type in a Django shell doesn't raise this exception. 

What does this exception apply to? 

I am under the impression that the model.save() ''force_insert/force_update'' arguments are there to get control over database operations. And as such I was expecting that force_update would work like a SQL UPDATE: Trying to overwrite a field with the same value is just fine. 

I'm submitting this as a ticket as I don't understand why it would be bad that an update didn't affect any rows. I don't care if there is any difference between the stored data and the model when I call .save() on a model. That would be application logic, I think. 

And as an aside: The MySQL database I'm using reports a ""0 rows affected"" on a SQL UPDATE statement with identical values. It doesn't return a warning or anything. "	Uncategorized	closed	Database layer (models, ORM)	1.6	Normal	invalid			Unreviewed	0	0	0	0	0	0