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[LDM #UDV-115196]: pqcat

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  • Subject: [LDM #UDV-115196]: pqcat
  • Date: Mon, 10 May 2010 14:04:25 -0600
Michael,

> Description of problem: Running pqcat -vl /tmp/pq.contents > /dev/null shows 
> me many entries in the queue for different versions of the same file.  For 
> example, in my queue I have many entries for a file named alert_wl.dat.  I 
> assumed there would be only one entry in the queue for a given file.  Why 
> would there be multiple entries with the same file name?

The data-products with the product-identifier "alert_w.data" must have 
different signatures.  The product-queue library won't add a data-product whose 
signature is equal to that of a data-product that's already in the 
product-queue.  The signature is usually the MD5 checksum of the data portion 
of the data-product (there are exceptions, however, see "pqinsert -i").  The 
signature is set by the process that inserted the data-product into the first 
product-queue.  Because the signature computation usually excludes the metadata 
portion of the data-product, it's possible for the product-queue to contain 
data-products with different data but with the same product-identifier.  We 
always advise that the product-identifier be unique.  Apparently, that advice 
isn't being followed in your case.

> Thanks,
> Michael

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: UDV-115196
Department: Support LDM
Priority: Normal
Status: Closed