From 7325d291524827806feed271a077ea23e2b1b21f Mon Sep 17 00:00:00 2001
From: Gagaro <gagaro42@gmail.com>
Date: Tue, 22 Mar 2022 09:11:46 +0100
Subject: [PATCH] Refs #30581 -- Fixed DatabaseFeatures.bare_select_suffix on
 MySQL < 8 and MariaDB < 10.4.

---
 django/db/backends/mysql/features.py | 11 +++++++++++
 tests/backends/tests.py              |  6 ++++++
 2 files changed, 17 insertions(+)

diff --git a/django/db/backends/mysql/features.py b/django/db/backends/mysql/features.py
index 357e431524e..834ea4f88f2 100644
--- a/django/db/backends/mysql/features.py
+++ b/django/db/backends/mysql/features.py
@@ -56,6 +56,17 @@ class DatabaseFeatures(BaseDatabaseFeatures):
         else:
             return (5, 7)
 
+    @cached_property
+    def bare_select_suffix(self):
+        if (
+            self.connection.mysql_is_mariadb and self.connection.mysql_version < (10, 4)
+        ) or (
+            not self.connection.mysql_is_mariadb
+            and self.connection.mysql_version < (8,)
+        ):
+            return " FROM DUAL"
+        return ""
+
     @cached_property
     def test_collations(self):
         charset = "utf8"
diff --git a/tests/backends/tests.py b/tests/backends/tests.py
index 28e00a04ca4..85b0e55cb01 100644
--- a/tests/backends/tests.py
+++ b/tests/backends/tests.py
@@ -548,6 +548,12 @@ class BackendTestCase(TransactionTestCase):
         )
         self.assertEqual(tuple(kwargs["extra"].values()), params[1:])
 
+    def test_queries_bare_where(self):
+        sql = f"SELECT 1{connection.features.bare_select_suffix} WHERE 1=1"
+        with connection.cursor() as cursor:
+            cursor.execute(sql)
+            self.assertEqual(cursor.fetchone(), (1,))
+
     def test_timezone_none_use_tz_false(self):
         connection.ensure_connection()
         with self.settings(TIME_ZONE=None, USE_TZ=False):