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Few questions. Can you please answer? Thanks.

 
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SreedharR

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Joined: 16 Jan 2009
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Location: syracuse

PostPosted: Tue Jan 20, 2009 6:33 pm    Post subject: Few questions. Can you please answer? Thanks.
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1) How do you set new version in DC region if you make changes to MPP (online program). In CICS, a command sets new version dynamically.
In IMS, do we need to stop and start the regions. What commands and steps we need to follow? If we have to stop the region, how we move the changes to production during daytime?

2) In manual, DLET, GHN, GNP, GHNP, GHU calls are not lsited under "Writing DL/I Calls for Transaction Management". Does it mean they cannot be used for MPP programs?

3) How do we invoke a DC program. I can see two ways. a) Issuing /FOR MODNAME b) /TRANSACTION NAME (MPP PROGRAM NAME)

In first case, does the map displayed first and then the program invoked next when user enters data and press any PFkey?

In second case, program invoked first, checks for SPA and outpurt mesage and if not present, sends map?

4) What is call sytax for inserting SPA and output message. If both are different, how do we know which one is which and can you please give an example?

5) What is single and multi segment output message. Generally, one screen shot is a mesage for MPP programs, right?

If so what does mean multi segment output message and why we need it and how to use it?

6) If we issue a GU call (qualified SSA) which satisfies more than one segment selection, does IMS create a temporary table of all the segments that satisfy the call and we can issue GN calls to select one by one. (Like DB2 cursor).
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Sandy Zimmer

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PostPosted: Tue Jan 20, 2009 6:40 pm    Post subject:
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I think you need to study a little bit more. IMS is completely different from CICS. DLI calls are database calls and have not a thing to do with transaction or DC calls. Why are you using a SPA? DO not use multi segment output messages. Is there someone at your installation that can be your mentor?
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SreedharR

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PostPosted: Wed Jan 21, 2009 9:47 am    Post subject:
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Thanks Sandy for the reply. I tried to search answers for the above questions, but could not get any straight answers. No, I do not have any mentor at this time.

I know you worked in IMS for many years, can you please find a few minutes to answer them. Thay can helpful for others also.

I saw some of your posts advocating not to use SPA. If multiple programs are involved for a transaction, how do you store and pass the retrieved and calculated information between them, if you do not store it in SPA?

Thanks.
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Sandy Zimmer

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PostPosted: Wed Jan 21, 2009 3:56 pm    Post subject:
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Is this a class assignment or a real life situation? There are some that still use a SPA - they are NOT high transaction processing installations - for instance banks - airlines - and they are few. You can pass info in your linkage section if multiple programs are involved in 1 transaction. You can hide info on your screen - in your message. Remember that there can be many people using the same program in the region. Once you send a message and then get a message, the data contained in your buffer may not be your data.
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SreedharR

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PostPosted: Wed Jan 21, 2009 7:28 pm    Post subject:
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Is SPA not unique to each logical (physical) terminal?

When we insert SPA, LTERM field in IO PCB mask indicates to which terminal message queue the SPA should send, right? Even multiple users use the same transaction at different terminals, the SPA is unique to each terminal, as LTERM is different for each user.

Am I missing something here? Thanks.
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Sandy Zimmer

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PostPosted: Wed Jan 21, 2009 8:02 pm    Post subject:
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The SPA area is a holdover from CICS. I only saw a handful of programs way back in the 1980's that dealt with SPA areas. It is not unique to a specific terminal but to a specific transaction and user. Never-ever-ever define anything terminal specific.
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SreedharR

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PostPosted: Wed Jan 21, 2009 9:42 pm    Post subject:
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I am somewhat not agreeing with you on SPA concept.

Let say, a single MPP displays two screens one after another. If user enters data on first screen and all the data get validated, the program has to store the first screen data somewhere and then displays the second screen for the user to enter additional data on the second one.

If you do not use SPA, how can you proceed in this case?
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Sandy Zimmer

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PostPosted: Wed Jan 21, 2009 11:01 pm    Post subject:
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Hidden key fields on your screen - message - databases. If you want a job with a bank or high transaction processor, you cannot use a SPA. I do not care if you agree - facts are facts. SPA areas can be defined as either in-core or disk. In either case, it is spelled PIG.
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SreedharR

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PostPosted: Thu Jan 22, 2009 1:27 am    Post subject:
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Still can't agree with you. Anyway my final argument. I am not saying SPA is the solution for every situation, but in some, I feel it might be only the option.

1) If one to use use hidden screen fields, not easy to find space to fit one screen full information on other, especially if the screen fields are packed.
This technique may work for small amount of information.

2) If we try to use database store, not sure issuing DB IO call is efficient than inserting/retrieving SPA.

Can you please provide answers to other questions if you find some time? Thanks.
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Sandy Zimmer

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PostPosted: Thu Jan 22, 2009 1:33 am    Post subject:
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You are not the one to decide whether or not to use a SPA - they are standards set by the company you work for. You should not mix the 2 in the same environment.
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dick scherrer

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Joined: 23 Nov 2006
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PostPosted: Thu Jan 22, 2009 1:56 am    Post subject:
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Hello,

Quote:
I feel it might be only the option.
That would be your own personal assessment. Keep in mind that you have extremely limited experience and as such your approach/tendancy will often be to use the first/easiest solution you discover. This will quite often not be in the best interest of your organization.

Many excuses can be offered for using bad design.

Suggest you rapidly move past this.
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