python - django.db.utils.OperationalError : (1071, 'Specified key was too long; max key length is 767 bytes' )

Question

我的模型:

class Course(models.Model):
    language = models.ForeignKey(Language)
    name = models.CharField(max_length=50, unique=True, default='course')
    title = models.CharField(max_length=1024, default='no title')
    foreign_title = models.CharField(max_length=1024, default='no title', blank=True)
    header = models.CharField(max_length=1024, default='', blank=True)
    description = models.TextField(null=True, blank=True)

    def __str__(self):
        return self.title

    def __unicode__(self):
        return u'%s' % self.title

我添加“unique_together”:

class Course(models.Model):
    language = models.ForeignKey(Language)
    name = models.CharField(max_length=50, unique=True, default='course')
    title = models.CharField(max_length=1024, default='no title')
    foreign_title = models.CharField(max_length=1024, default='no title', blank=True)
    header = models.CharField(max_length=1024, default='', blank=True)
    description = models.TextField(null=True, blank=True)

    class Meta:
        unique_together = ['language', 'name', 'title']

    def __str__(self):
        return self.title

    def __unicode__(self):
        return u'%s' % self.title

迁移中出现错误的时间:

 django.db.utils.OperationalError: (1071, 'Specified key was too long; max key length is 767 bytes')

我的数据库是: mysql Ver 15.1 Distrib 10.0.17-MariaDB，用于使用 readline 5.2 的 debian-linux-gnu (x86_64)

我尝试增加索引mysql的长度:

MariaDB [(none)]> set global innodb_file_format = BARRACUDA;
Query OK, 0 rows affected (0.00 sec)

MariaDB [(none)]> set global innodb_large_prefix = ON;
Query OK, 0 rows affected (0.00 sec)

但这还不够:

django.db.utils.OperationalError: (1071, 'Specified key was too long; max key length is 3072 bytes')

问题索引长度。如何指定Django索引的长度限制？

Answer 1

解决办法是

ALTER DATABASE `databasename` CHARACTER SET utf8;