How to create alternate index for ESDS

vch · New User Joined: 01 Feb 2008 Posts: 22 Location: chennai

Hi,
how to create alternate index for ESDS..?

what is the difference between QSAM and ESDS??

Gnanas N · Posted: Fri Mar 21, 2008 3:43 pm

I think of these.

Sequential(QSAM) files can be created on tape while ESDS files cannot.

Also, you can have ALTINDEX for an ESDS while no such facility exists for QSAM files.

You can this for creating alternate index.

dbzTHEdinosauer · Posted: Fri Mar 21, 2008 3:51 pm

gnanas,

what would be the key? how would you define it?

Gnanas N · Posted: Fri Mar 21, 2008 4:08 pm

Dick,

Alternate Index Key Type for ESDS may be either Unique key or
Nonunique key

Please correct me if I am worng.

vch · New User Joined: 01 Feb 2008 Posts: 22 Location: chennai

ganas,

how to define alternate index for ESDS? can you give me full syntax for taht?

Gnanas N · Posted: Fri Mar 21, 2008 5:59 pm

This link might give you more information.

publib.boulder.ibm.com/infocenter/pdthelp/v1r1/index.jsp?topic=/com.ibm.entpli4.doc/ibma1mst266.htm

Marso · Posted: Sun Mar 23, 2008 7:40 pm

Anuj Dhawan · Posted: Sun Mar 23, 2008 11:53 pm

Hi,

It seems relevant to have a definition of ESDS here:

Anuj Dhawan · Posted: Mon Mar 24, 2008 12:04 am

Hi,

A little more, sometimes I'm not satisfied of myself and keep pouring in..

An ESDS is essentially a sequential dataset where new records are always inserted at the end. You cannot access records directly with a key. However, you may access specific records with a relative byte address (RBA), if you have or can calculate it. In fact, it's fairly common to see CICS application use an ESDS as a log file to write records in sequential order while retrieving the new record's RBA from the RIDFLD operand of the EXEC CICS WRITE command. If the application squirrels away the RBA it can later retrieve the log record directly. Also note that you cannot physically delete a record from an ESDS. Instead, most applications utilize a "logical delete" scheme where a field in the ESDS record is set to a value indicating the record is no longer valid.

enrico-sorichetti · Posted: Mon Mar 24, 2008 12:24 am

/ generic invitation on
please please review your vsam

From the manual

the_gautam · Posted: Mon Mar 24, 2008 8:26 am

here is a sample JCL to create the altenate Index on an ESDS.

dbzTHEdinosauer · Posted: Tue Mar 25, 2008 12:57 pm

that is what I like about this forum: reality or truth does not matter; each will continue to prattle-on showing how much he/she knows, when in reality, few can read, much less give a good answer.

Anuj Dhawan · Posted: Tue Mar 25, 2008 2:02 pm

Hi,

Not sure if I'm also a victim here in this thread, if any how yes, please put your comments in, so that I can learn something new.

dbzTHEdinosauer · Posted: Tue Mar 25, 2008 2:14 pm

Anuj D.,

The only Victims in this thread are those (like yourself) who continue to post meaningful and correct information.

It has only been stated 3 times (by different individuals) that an ESDS dataset does not have 'ALTERNATE' nor 'PRIMARY' index. But, others continue to post 'JCL' to create that which is not 'creatable'.

But that is why these threads are so long. Few people bother to read, they are too busy posting.

vch · New User Joined: 01 Feb 2008 Posts: 22 Location: chennai

Thanks alot for all your responses..

I created an alternate index to an ESDS file successfully.

so it is confirmed that we can create an ESDS to an ESDS file.

vch · New User Joined: 01 Feb 2008 Posts: 22 Location: chennai

so it is confirmed that we can create an AIX to an ESDS file

dbzTHEdinosauer · Posted: Tue Mar 25, 2008 4:20 pm

just as soon as you have tested it and can prove that it works!

enrico-sorichetti · Posted: Tue Mar 25, 2008 5:54 pm

here is the jcl tested and working

dbzTHEdinosauer · Posted: Tue Mar 25, 2008 6:16 pm

enrico-sorichetti · Posted: Tue Mar 25, 2008 6:25 pm

I have shown how...
define an esds cluster
print the esds cluster
9
7
5
3
1
8
6
2
0
repro some data in it
define the aix
build the aix
define a path
priint/access the base cluster thru a path
0
1
2
3
4
5
6
7
8
9

here is the jcl and the sysout of printing the AIX and the rba is right there

jcl

enrico-sorichetti · Posted: Tue Mar 25, 2008 6:42 pm

Add on' s to my previous post