[1.11.x] Refs #28876 -- Fixed incorrect class-based model index name generation for models with quoted db_table.

Thanks Simon Charette and Tim Graham for the review and Carlos E. C.
Leite for the report.

Backport of f79d9a322c6008e5fada1453aebfb56afc316cc8 from master

1 files changed, 2 insertions, 1 deletions

diff --git a/django/db/models/indexes.py b/django/db/models/indexes.py
index 0ee2bf3610..7cda26508e 100644
--- a/django/db/models/indexes.py
+++ b/django/db/models/indexes.py
@@ -2,6 +2,7 @@ from __future__ import unicode_literals
 
 import hashlib
 
+from django.db.backends.utils import split_identifier
 from django.utils.encoding import force_bytes
 
 __all__ = [str('Index')]
@@ -101,7 +102,7 @@ class Index(object):
         (8 chars) and unique hash + suffix (10 chars). Each part is made to
         fit its size by truncating the excess length.
         """
-        table_name = model._meta.db_table
+        _, table_name = split_identifier(model._meta.db_table)
         column_names = [model._meta.get_field(field_name).column for field_name, order in self.fields_orders]
         column_names_with_order = [
             (('-%s' if order else '%s') % column_name)