From 9af6c97504ef2b06dd5292d03ea94d3eb5d8c4d6 Mon Sep 17 00:00:00 2001
From: Mariusz Felisiak <felisiak.mariusz@gmail.com>
Date: Thu, 1 Jun 2017 11:51:02 +0200
Subject: [PATCH] Refs #26682 -- Added AutoField introspection on Oracle.

---
 django/db/backends/oracle/features.py      |  1 +
 django/db/backends/oracle/introspection.py | 23 +++++++++++++++-------
 docs/releases/2.0.txt                      |  3 +++
 3 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/django/db/backends/oracle/features.py b/django/db/backends/oracle/features.py
index af95136fa7..fe6e30dc46 100644
--- a/django/db/backends/oracle/features.py
+++ b/django/db/backends/oracle/features.py
@@ -11,6 +11,7 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     has_select_for_update_skip_locked = True
     can_return_id_from_insert = True
     allow_sliced_subqueries = False
+    can_introspect_autofield = True
     supports_subqueries_in_group_by = False
     supports_transactions = True
     supports_timezones = False
diff --git a/django/db/backends/oracle/introspection.py b/django/db/backends/oracle/introspection.py
index 50d9d8092c..f15b49eb19 100644
--- a/django/db/backends/oracle/introspection.py
+++ b/django/db/backends/oracle/introspection.py
@@ -1,12 +1,15 @@
 import warnings
+from collections import namedtuple
 
 import cx_Oracle
 
 from django.db.backends.base.introspection import (
-    BaseDatabaseIntrospection, FieldInfo, TableInfo,
+    BaseDatabaseIntrospection, FieldInfo as BaseFieldInfo, TableInfo,
 )
 from django.utils.deprecation import RemovedInDjango21Warning
 
+FieldInfo = namedtuple('FieldInfo', BaseFieldInfo._fields + ('is_autofield',))
+
 
 class DatabaseIntrospection(BaseDatabaseIntrospection):
     # Maps type objects to Django Field types.
@@ -32,9 +35,11 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
             precision, scale = description[4:6]
             if scale == 0:
                 if precision > 11:
-                    return 'BigIntegerField'
+                    return 'BigAutoField' if description.is_autofield else 'BigIntegerField'
                 elif precision == 1:
                     return 'BooleanField'
+                elif description.is_autofield:
+                    return 'AutoField'
                 else:
                     return 'IntegerField'
             elif scale == -127:
@@ -61,12 +66,16 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
                 CASE
                     WHEN char_used IS NULL THEN data_length
                     ELSE char_length
-                END as internal_size
+                END as internal_size,
+                CASE
+                    WHEN identity_column = 'YES' THEN 1
+                    ELSE 0
+                END as is_autofield
             FROM user_tab_cols
             WHERE table_name = UPPER(%s)""", [table_name])
         field_map = {
-            column: (internal_size, default if default != 'NULL' else None)
-            for column, default, internal_size in cursor.fetchall()
+            column: (internal_size, default if default != 'NULL' else None, is_autofield)
+            for column, default, internal_size, is_autofield in cursor.fetchall()
         }
         self.cache_bust_counter += 1
         cursor.execute("SELECT * FROM {} WHERE ROWNUM < 2 AND {} > 0".format(
@@ -75,14 +84,14 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
         description = []
         for desc in cursor.description:
             name = desc[0]
-            internal_size, default = field_map[name]
+            internal_size, default, is_autofield = field_map[name]
             name = name % {}  # cx_Oracle, for some reason, doubles percent signs.
             description.append(FieldInfo(*(
                 (name.lower(),) +
                 desc[1:3] +
                 (internal_size, desc[4] or 0, desc[5] or 0) +
                 desc[6:] +
-                (default,)
+                (default, is_autofield)
             )))
         return description
 
diff --git a/docs/releases/2.0.txt b/docs/releases/2.0.txt
index 6666f6d1d5..1070889da0 100644
--- a/docs/releases/2.0.txt
+++ b/docs/releases/2.0.txt
@@ -195,6 +195,9 @@ Management Commands
 * The new :option:`diffsettings --output` option allows formatting the output
   in a unified diff format.
 
+* On Oracle, :djadmin:`inspectdb` can now introspect ``AutoField`` if the
+  column is created as an identity column.
+
 Migrations
 ~~~~~~~~~~