When merging unrelated Git histories, the merge driver uses an empty
ancestor database. Thus, the SQL max function cannot operate and
returns a null value during the merge, effectively discarding our
database during the merge. This PR ignores the ancestor database if
it is empty, so both histories are fully preserved in this corner case.
When merging unrelated Git histories, the merge driver uses an empty ancestor database. Thus, the SQL
maxfunction cannot operate and returns anullvalue during the merge, effectively discarding our database during the merge. This PR ignores the ancestor database if it is empty, so both histories are fully preserved in this corner case.