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
31186	Error updating unique field	Kailegh	nobody	"Hi, I think I have discovered a bug, if you have a field like the following:
{{{
audio_name = models.CharField(blank=False, max_length=255)
}}}
and decide to change it to the following one:
{{{
audio_name = models.TextField(blank=False)
}}}
it generates the following migration code:
{{{
   operations = [
        migrations.AlterModelOptions(
            name='s3_bucket_audios',
            options={},
        ),
        migrations.AlterField(
            model_name='s3_bucket_audios',
            name='audio_name',
            field=models.TextField(help_text='name of the audio in the s3 bucket'),
        ),
        migrations.AlterUniqueTogether(
            name='s3_bucket_audios',
            unique_together=set(),
        ),
    ]
}}}
However it that field was being use in a unique condition:
{{{
class Meta:
   ordering = [ ""audio_name""]
   unique_together = ('audio_name')
}}}
you get the following error:
{{{
django.db.utils.OperationalError: (1170, ""BLOB/TEXT column 'audio_name' used in key specification without a key length"")
}}}
That is because it changes the field type before changing the unique condition, I think the order should be handled automatically, I had to change the code manually to:
{{{
   operations = [
        migrations.AlterModelOptions(
            name='s3_bucket_audios',
            options={},
        ),
        migrations.AlterUniqueTogether(
            name='s3_bucket_audios',
            unique_together=set(),
        ),
        migrations.AlterField(
            model_name='s3_bucket_audios',
            name='audio_name',
            field=models.TextField(help_text='name of the audio in the s3 bucket'),
        ),
    ]
}}}

It is not a big issue anyway...
Thanks a lot for your amazing work!!"	Bug	new	Migrations	2.2	Normal		migration, TextField, CharField		Unreviewed	0	0	0	0	0	0