Fixed #27458 -- Fixed invalid sequence/index names when using "USER"."TABLE" db_table on Oracle.

django/contrib/gis/db/backends/oracle/schema.py

 from django.contrib.gis.db.models.fields import GeometryField
 from django.db.backends.oracle.schema import DatabaseSchemaEditor
-from django.db.backends.utils import truncate_name
+from django.db.backends.utils import strip_quotes, truncate_name
 
 
 class OracleGISSchemaEditor(DatabaseSchemaEditor):
@@ -91,4 +91,4 @@ class OracleGISSchemaEditor(DatabaseSchemaEditor):
     def _create_spatial_index_name(self, model, field):
         # Oracle doesn't allow object names > 30 characters. Use this scheme
         # instead of self._create_index_name() for backwards compatibility.
-        return truncate_name('%s_%s_id' % (model._meta.db_table, field.column), 30)
+        return truncate_name('%s_%s_id' % (strip_quotes(model._meta.db_table), field.column), 30)

django/db/backends/base/schema.py

@@ -2,6 +2,7 @@ import hashlib
 import logging
 from datetime import datetime
 
+from django.db.backends.utils import strip_quotes
 from django.db.transaction import TransactionManagementError, atomic
 from django.utils import six, timezone
 from django.utils.encoding import force_bytes
@@ -841,7 +842,7 @@ class BaseDatabaseSchemaEditor(object):
         The name is divided into 3 parts: the table name, the column names,
         and a unique digest and suffix.
         """
-        table_name = model._meta.db_table
+        table_name = strip_quotes(model._meta.db_table)
         hash_data = [table_name] + list(column_names)
         hash_suffix_part = '%s%s' % (self._digest(*hash_data), suffix)
         max_length = self.connection.ops.max_name_length() or 200

django/db/backends/oracle/operations.py

@@ -6,7 +6,7 @@ import uuid
 
 from django.conf import settings
 from django.db.backends.base.operations import BaseDatabaseOperations
-from django.db.backends.utils import truncate_name
+from django.db.backends.utils import strip_quotes, truncate_name
 from django.utils import six, timezone
 from django.utils.encoding import force_bytes, force_text
 
@@ -450,11 +450,13 @@ WHEN (new.%(col_name)s IS NULL)
 
     def _get_sequence_name(self, table):
         name_length = self.max_name_length() - 3
-        return '%s_SQ' % truncate_name(table, name_length).upper()
+        sequence_name = '%s_SQ' % strip_quotes(table)
+        return truncate_name(sequence_name, name_length).upper()
 
     def _get_trigger_name(self, table):
         name_length = self.max_name_length() - 3
-        return '%s_TR' % truncate_name(table, name_length).upper()
+        trigger_name = '%s_TR' % strip_quotes(table)
+        return truncate_name(trigger_name, name_length).upper()
 
     def bulk_insert_sql(self, fields, placeholder_rows):
         return " UNION ALL ".join(

django/db/backends/utils.py

@@ -209,3 +209,13 @@ def format_number(value, max_digits, decimal_places):
     if decimal_places is not None:
         return "%.*f" % (decimal_places, value)
     return "{:f}".format(value)
+
+
+def strip_quotes(table_name):
+    """
+    Strip quotes off of quoted table names to make them safe for use in index
+    names, sequence names, etc. For example '"USER"."TABLE"' (an Oracle naming
+    scheme) becomes 'USER"."TABLE'.
+    """
+    has_quotes = table_name.startswith('"') and table_name.endswith('"')
+    return table_name[1:-1] if has_quotes else table_name

django/db/models/fields/related.py

@@ -1565,7 +1565,8 @@ class ManyToManyField(RelatedField):
         elif self.db_table:
             return self.db_table
         else:
-            return utils.truncate_name('%s_%s' % (opts.db_table, self.name), connection.ops.max_name_length())
+            m2m_table_name = '%s_%s' % (utils.strip_quotes(opts.db_table), self.name)
+            return utils.truncate_name(m2m_table_name, connection.ops.max_name_length())
 
     def _get_m2m_attr(self, related, attr):
         """

tests/schema/tests.py

@@ -2266,3 +2266,34 @@ class SchemaTests(TransactionTestCase):
             editor, Author, tob_auto_now_add, 'tob_auto_now_add', now.time(),
             cast_function=lambda x: x.time(),
         )
+
+    @unittest.skipUnless(connection.vendor == 'oracle', 'Oracle specific db_table syntax')
+    def test_creation_with_db_table_double_quotes(self):
+        oracle_user = connection.creation._test_database_user()
+
+        class Student(Model):
+            name = CharField(max_length=30)
+
+            class Meta:
+                app_label = 'schema'
+                apps = new_apps
+                db_table = '"%s"."DJANGO_STUDENT_TABLE"' % oracle_user
+
+        class Document(Model):
+            name = CharField(max_length=30)
+            students = ManyToManyField(Student)
+
+            class Meta:
+                app_label = 'schema'
+                apps = new_apps
+                db_table = '"%s"."DJANGO_DOCUMENT_TABLE"' % oracle_user
+
+        self.local_models = [Student, Document]
+
+        with connection.schema_editor() as editor:
+            editor.create_model(Student)
+            editor.create_model(Document)
+
+        doc = Document.objects.create(name='Test Name')
+        student = Student.objects.create(name='Some man')
+        doc.students.add(student)