add unique=True to slug in product

store/migrations/0055_auto_20170224_1244.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.3 on 2017-02-24 12:44
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('store', '0054_auto_20160715_1811'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='product',
+            name='slug',
+            field=models.SlugField(default='', max_length=256, unique=True, verbose_name='Ссылка'),
+        ),
+    ]

store/models.py

@@ -182,7 +182,7 @@ class Brand(models.Model):
 
 class Product(models.Model):
     title = models.CharField('Наименование', max_length=256, default='')
-    slug = models.SlugField('Ссылка', max_length=256, default='')
+    slug = models.SlugField('Ссылка', max_length=256, default='', unique=True)
     categories = models.ManyToManyField(
         Category, verbose_name='Категории', related_name='products')
     description = models.TextField(