diff --git a/django/db/backends/oracle/base.py b/django/db/backends/oracle/base.py
index 7a152ea0187..5ceddf40d84 100644
--- a/django/db/backends/oracle/base.py
+++ b/django/db/backends/oracle/base.py
@@ -717,6 +717,16 @@ class DatabaseWrapper(BaseDatabaseWrapper):
 
     @cached_property
     def version_has_default_introspection_bug(self):
+        """
+        Some versions of Oracle -- we've seen this on 11.2.0.1 and suspect
+        it goes back -- have a weird bug where, when an integer column is
+        defined with a default, its precision is later reported on introspection
+        as 0, regardless of the real precision. For Django introspection, this
+        means that such columns are reported as IntegerField even if they are
+        really BigIntegerField or BooleanField.
+
+        The bug is solved in Oracle 11.2.0.2 and up.
+        """
         return self.oracle_full_version < '11.2.0.2'