What is the significance of having a ESDS with "FIRST R

arulraj_samuel · New User Joined: 05 Mar 2007 Posts: 6 Location: Chennai

Hi,

What is the significance of having a ESDS with "FIRST REF" option? Will it allow updating an ESDS as an inquiry is done.

Arul

expat · Posted: Tue May 13, 2008 6:55 pm

Where is "FIRST REF" mentioned in the IDCAMS manual ?

mytags · New User Joined: 28 Apr 2008 Posts: 63 Location: US

Hi Arul,
Can you please post question with full details?
hari

arulraj_samuel · New User Joined: 05 Mar 2007 Posts: 6 Location: Chennai

Hi Hari,

My requirement is to process a ESDS file thru Batch Jobs, ESDS file under discussion is allocated to CICS region as well. So any updates by online region to this file may be missed out since the file will be occupied Batch Job. To avoid it, if we have the ESDS closed with "Open with First Ref" option, then any update to the ESDS file while the batch job is in progress can be captured. Here the significance of "Open with First Ref" option is not clear.

Can you please explain it?

Arul

enrico-sorichetti · Posted: Thu May 15, 2008 5:12 pm

FIRST REF is not an IDCAMS option...
it' s a CICS dataset definition attribute...
it simply means ... if the dataset is closed open it the first time it is being used

google with "CICS OPEN WITH FIRST REF"
or look at the relevant CICS documentation
(something like Resource definition Manual)

strange... an ESDS cluster used under CICS

dbzTHEdinosauer · Posted: Thu May 15, 2008 5:32 pm

enrico,

back in the late 70's early 80's, we found that ksds files (with large records) were really slow. So, we would use an esds file for the master and use a ksds as the index to the esds. the ksds (index file) was small enough that most of it was available in memory, so acccess the ksds by key, use the rba (contained in data portion of ksds record) to access the esds.