020 field contains duplicate data error or reappearing ISBNs
Symptom
- A record does not validate. An error message appears, something like the below:
020 occurrence [x], $a occurrence [x] - contains duplicate data
020 occurrence [x], $a occurrence [x] - contains duplicate data - Every time you try to delete or convert the field so that there is one occurrence, it gets put back.
Applies to
- Connexion
- Gestione record WorldShare
Resolution
ISBNs appear in pairs in most WorldCat records. The 10-digit and 13-digit ISBNs both appear. Both must be either deleted or changed to $z. If the 10-digit one is left in the record in subfield a, then the 13-digit will be automatically generated for the subfield a.
You may need to change both the 10-digit and the 13-digit to $z. Or, you may need to delete the 10-digit 020 field when putting the 13-digit one in $z.