check_doc_unique_index does not find duplicate ISBNs when it has additional info

• Article Type: General
• Product: Aleph
• Product Version: 14.2

Description:
The check_doc_unique_index does not find duplicate ISBNs when it has additional information (like pbk, acid paper, volume etc.) if this information is not in the index.
For example, if in the database there is ISBN 0080232582 (pbk.), and I will catalog another record with ISBN 0080232582, the check program will not find the existent record. Only if I catalog exactly the same ISBN (0080232582 (pbk.)), then the check will find it.
Also, if I catalog this ISBN with punctuation (like "0080232582 (pbk.) : ", the check will not find the duplicate. Why?

Resolution:
The check_doc_unique_index only identifies duplicate records with exactly the same text.
Other cases are not considered duplicates.
1. For example, two ISBNs with same number but with different additional information are not considered identical (for example, one is paperback and other is not).
2. Also, additional punctuation will be considered as different text.
3. But additional subfields (if are not part of the index) will be ignored and records will be considered duplicate (for example, $$c in field 020 for MARC21 , $$d in field 010 for UNIMARC).

4. Please note that the check_doc_unique_index program "reads" only the first line from tab11_ind. Therefore please make sure that your tab11_ind is set properly - for example, line
020 ISBN a
should precede the line:
020 ISBN z
if the check is done on $$a.

Please note:
this is the order of fields in tab11_ind:

If you change in SCD01's tab11_ind the order of the 2 lines:
010## ISBN z
010## ISBN a

changed to:
010## ISBN a
010## ISBN z

then it works (it generates the "duplicate index" message).