On 17 Nov 2015 10:23:30 -0800, in bit.listserv.ibm-main you wrote:

>On Tue, 17 Nov 2015 18:41:38 +0100, Lucas Rosalen wrote:
>
>>8th email on the thread describes why and the "problem" to solve....
>> 
>That seems to be: 
>https://listserv.ua.edu/cgi-bin/wa?A2=ind1511&L=ibm-main&P=344282
>Thanks.
>
>Keep an external index?
>
>z/OS UNIX directory search is fast; I don't know how it compares to Classic 
>catalog
>search.  Shadow your G00*V00 names with empty files in a UNIX directory and
>use that as an index.  Bizarre?  Well, before VSAM programmers used empty PDS
>members as similar placeholders.
>
>Directory search in z/OS may be faster than in competing UNIXen because z/OS
>indexes its directories.  Don't know about the others.
>
>And readdir() will return the smallest (oldest?) G00*V00 first, so you could
>bail out there.
>
>VSAM index?  PDSE with empty members used as index?  Deleting the lowest
>named PDS member is the worst performance case; don't know about PDSE.
>
>How many is "lots"?
>
>What makes "V00" ever Vnn, where N<>0?

Running a program that copies the file doing updating desired to a new
file such that it retains its relative position.  Actual generation
and version numbers are used.

//G00V00RP EXEC PGM=MYREPLAC
//INDD DD DSN=HLQ.MYGDG.G0001V00,DISP=OLD
//OUTDD DD DSN=HLQ.MYGDG.G0001V01,DISP=(NEW,CATLG)

Clark Morris
>
>-- gil
>
>----------------------------------------------------------------------
>For IBM-MAIN subscribe / signoff / archive access instructions,
>send email to [email protected] with the message: INFO IBM-MAIN

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO IBM-MAIN

Reply via email to