[1.8.x] Fixed #24729 -- Removed test db flush when using --keepdb.

django/db/backends/base/creation.py

@@ -365,7 +365,7 @@ class BaseDatabaseCreation(object):
             verbosity=max(verbosity - 1, 0),
             interactive=False,
             database=self.connection.alias,
-            test_flush=True,
+            test_flush=not keepdb,
         )
 
         # We then serialize the current state of the database into a string

docs/releases/1.8.1.txt

@@ -75,6 +75,9 @@ Bugfixes
 * Fixed a migration crash when renaming the target model of a many-to-many
   relation (:ticket:`24725`).
 
+* Removed flushing of the test database with :djadminopt:`--keepdb`, which
+  prevented apps with data migrations from using the option (:ticket:`24729`).
+
 Optimizations
 =============