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#1: ims db to db2 conversion Author: nadh,

Posted: Wed Oct 13, 2004 3:00 am
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Hi,

can anyone send me the IMS DB to DB2 conversion code. I mean code showing the DLI call and corresponding DB2 CODE.

Its bit urgent.. and can send to this id hvj04@yahoo.com..

Thanks in advance.

venkat[/b]

#2: Author: kolusu, Location: San Jose

Posted: Wed Oct 13, 2004 4:33 am
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nadh,

I am assuming that the tables are already created for the corresponding segments in the IMS database . Relate the IMS calls to DB2.

GU, GHN, GHU are all simply SELECT in DB2

ISRT is equivalent to INSERT

REPL is equivalent to UPDATE

DLET is equivalent to DELETE.

So in your program wherever there is a IMS call , simply add the respective statement after it.

Hope this helps...

Cheers

Kolusu

#3: Author: Bithead, Location: Michigan, USA

Posted: Wed Oct 13, 2004 9:19 am
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Remember that sequential reads thru segments in an IMS database should be converted to use cursors.

Straight replacement of IMS calls with DB2 calls often leads to inefficient and slower code.

#4: Author: karthikbabudh,

Posted: Mon May 02, 2005 7:44 am
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Hi Kolusu,
If Command codes are involved in a Call. then how to code that in DB2

#5: Author: vjkumk,

Posted: Sun Aug 12, 2007 7:48 am
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please anybody explain what is the equavalent db2 operations for ims command code calls .

cheers,
vj

#6: Author: kolusu, Location: San Jose

Posted: Mon Aug 13, 2007 6:10 am
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vjkumk,

It depends. Command codes in IMS are equivalent to JOINS in DB2 if each segment in IMS is changed to a DB2 table. Sometimes you can achieve the end result by using a subquery also.

Kolusu

#7: Author: vjkumk,

Posted: Tue Aug 14, 2007 9:37 pm
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Thanks kolusu.

cheers,vj

#8: Author: misi01, Location: Stockholm, Sweden

Posted: Wed Mar 29, 2017 3:36 am
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I've done this twice; once for converting card purchases/ATM withdrawals from DL/1 to DB2 (a HUGE job) and once for a smaller, simpler system.

There is no simple, one size fits all methodology. First of all, your DBA will need to analyze the DL/1 database and possibly "convert" it to DB2 tables with all the normalization that includes. This in turn means that a DL/1 call does NOT necessarily convert straight off to a simple DB2 select. You might end up having to do a join between two or more tables. In addition, an insert might require that you specify a timestamp for your insert, something that might not be included in the old DL/1 code.

One very important piece of advice I WOULD give you though (depending on the importance of the system being converted). Ensure your code can flip-flop between DL/1 and DB2 and/or both. That means that when you go live, you can test your DB2 code, and at the first hint of problems, you simply revert to the DL/1 code instead and everything works as expected. (We had recourse to this when our first attempt failed)

Update It was only just now I noticed how OLD the original append was. The comments in THIS append still stand though if anyone else needs to go through such a conversion.

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