Question

Can the following values be duplicated in Aleph?

* Patron barcodes

* Other patron IDs

* Item barcodes

* Invoice numbers

* Order numbers   

Answer

*  Patron barcodes

<<  No.  The Z308_REC_KEY is defined as UNIQUE in Oracle, so there could only be one “01nnnnnnnnnnnnnnnnnn” record.  (“01” is the Z308-KEY-TYPE for the patron barcode.)

*  Other patron IDs

<<  No.  Same as above.  The Z308_REC_KEY is defined as UNIQUE in Oracle.  See also, article "Duplicate patron ID's *MASTER RECORD*"  :  https://knowledge.exlibrisgroup.com/...MASTER_RECORD*

*  Item barcodes

<<  Yes.  The Z30_BARCODE is usually defined as NONUNIQUE, but, as described in the article “Duplicate item barcodes” , the  tab100 CHECK-BARCODE=Y parameter usually prevents this.

*  Invoice numbers

<<  The Z77_REC_KEY is defined as UNIQUE.  The  Z77_REC_KEY consists of:

            03 Z77-VENDOR-CODE          PICTURE X(20).

            03 Z77-INVOICE-NUMBER       PICTURE X(15).

   So, though one *could* have a duplicate Z77-INVOICE-NUMBER, since Aleph uses that number only in conjunction with the Z77-VENDOR-CODE, the invoice number is effectively unique.   

*  Order numbers   

<<  Yes.  The Z68_ORDER_NUMBER is defined as NONUNIQUE.   {The z68_rec_key (the Aleph order record key) is UNIQUE.}

But uniqueness is normally enforced via the "last-order-number" util g/2 counter.  See article "Duplicate Order Numbers" : https://knowledge.exlibrisgroup.com/..._Order_Numbers .