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
24410	MySQL manually created indexes aren't recognized	László Károlyi	nobody	"Hey,

Using Django 1.7's migrations with MySQL, when I need to create a custom index on a column (`Specified key was too long; max key length is 767 bytes`, thus the column needs a prefix length), it's not recognized, not deleted when migrating backwards and the erroneous index creation SQL is recreated in the next migration, causing the migration to fail, or creating another index which emits a MySQL warning (`_mysql_exceptions.Warning: Duplicate index 'cdn_image_cdn_path_2654d3de68657258_uniq' defined on the table 'xxx.cdn_image'. This is deprecated and will be disallowed in a future release.`), thus causing the migration to fail.

Here's the model:

{{{
class Image(models.Model):

    """"""Model for the saved images""""""

    comment = models.ManyToManyField(
        'base.Comment', null=None, default=1, verbose_name=_('Found in comment'))
    orig_src = models.URLField(
        verbose_name=_('Original source'), max_length=512, db_index=True)
    mime_type = models.CharField(verbose_name=_('Mime type'), max_length=100)
    cdn_path = models.CharField(
        verbose_name=_('Path in CDN'), max_length=255, unique=True)
    file_hash = models.CharField(
        verbose_name=_('File hash'), max_length=200, unique=True)

    def __str__(self):
        return self.cdn_path
}}}"	Uncategorized	new	Uncategorized	1.7	Normal				Unreviewed	0	0	0	0	0	0