diff --git a/abrechnung/database/revisions/0017_clean_non_nullable_strings.sql b/abrechnung/database/revisions/0017_clean_non_nullable_strings.sql
new file mode 100644
index 00000000..300e6c92
--- /dev/null
+++ b/abrechnung/database/revisions/0017_clean_non_nullable_strings.sql
@@ -0,0 +1,7 @@
+-- revision: 04424b59
+-- requires: a83f4798
+
+alter table transaction_history alter column description set default '';
+alter table transaction_history alter column description set not null;
+
+alter table grp alter column created_by set not null;
\ No newline at end of file