diff --git a/installer/data/mysql/db_revs/220600048.pl b/installer/data/mysql/db_revs/220600048.pl
index 9c35ccec5d..8fb5e9c322 100755
--- a/installer/data/mysql/db_revs/220600048.pl
+++ b/installer/data/mysql/db_revs/220600048.pl
@@ -6,6 +6,11 @@ return {
     up => sub {
         my ($args) = @_;
         my ($dbh, $out) = @$args{qw(dbh out)};
+
+        # Delete 'empty' guarantors. No longer possible to add them via interface. Have no use.
+        $dbh->do(q{
+DELETE FROM borrower_relationships WHERE guarantor_id IS NULL
+        });
         $dbh->do(q{
 ALTER TABLE borrower_relationships CHANGE COLUMN guarantor_id guarantor_id int(11) NOT NULL
         });