diff --git a/docs/topics/migrations.txt b/docs/topics/migrations.txt index b1531a54b9b..a188ea10c2b 100644 --- a/docs/topics/migrations.txt +++ b/docs/topics/migrations.txt @@ -340,7 +340,9 @@ They will, however, have the same fields, relationships and ``Meta`` options References to functions in field options such as ``upload_to`` and ``limit_choices_to`` are serialized in migrations, so the functions will need -to be kept around for as long as there is a migration referencing them. +to be kept around for as long as there is a migration referencing them. Any +:doc:`custom model fields ` will also need to be +kept, since these are imported directly by migrations. In addition, the base classes of the model are just stored as pointers, so you must always keep base classes around for as long as there is a migration