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
24934	Can't drop or change unique_together index	user0007	nobody	"Hello,

I'm using Django 1.8.2 and Mysql 5.6. I created model with two fields in unique_together:


{{{
    user = models.ForeignKey(User)
    product = models.ForeignKey(Product)

    class Meta:
        unique_together = ('user', 'product')
}}}

the table was created successfully with following indexes:

{{{
PRIMARY                                     |            1 | id
myapp_mymodel_user_id_16c33dde7f7257bb_uniq |            1 | user_id
myapp_mymodel_user_id_16c33dde7f7257bb_uniq |            2 | product_id
myapp_mymodel_1ba366c5                      |            1 | user_id
myapp_mymodel_9bea82de                      |            1 | product_id
}}}

Later I removed unique_together from my model:

{{{
    class Meta:
        pass
}}}

so Django generated a migration:

{{{
    operations = [
        migrations.AlterUniqueTogether(
            name='mymodel',
            unique_together=set([]),
        ),
    ]
}}}

but when i try to apply this migrattion I have got an error:

{{{
    django.db.utils.OperationalError: (1061, ""Duplicate key name 'myapp_mymodel_1ba366c5'"")
}}}

Django is trying to create this index, instead of removed them.

The same situation is when I try to add third field to my unique_together list:

{{{
    class Meta:
        unique_together = ('user', 'product', 'category')
}}}

{{{
    django.db.utils.OperationalError: (1061, ""Duplicate key name 'myapp_mymodel_1ba366c5'"")
}}}

PS. The table was created using Django 1.7.X but changes was made using Django 1.8.2"	Bug	closed	Migrations	1.8	Normal	fixed			Unreviewed	0	0	0	0	0	0