Portal | Manuals | References | Downloads | Info | Programs | JCLs | Master the Mainframes
IBM Mainframe Computers Forums Index
 
Register
 
IBM Mainframe Computers Forums Index Mainframe: Search IBM Mainframe Forum: FAQ Memberlist Usergroups Profile Log in to check your private messages Log in
 

 

Why 2 Databases(DB2 and Vsam) in a single application?

 
Post new topic   Reply to topic    IBMMAINFRAMES.com Support Forums -> Mainframe Interview Questions
View previous topic :: :: View next topic  
Author Message
haidude

New User


Joined: 11 May 2007
Posts: 10
Location: Mumbai

PostPosted: Tue Jun 12, 2007 10:16 am    Post subject: Why 2 Databases(DB2 and Vsam) in a single application?
Reply with quote

I have faced one interview in this below question.Why 2 databases in a single application(DB2 and Vsam),why not one database(either DB2 or Vsam)?
Back to top
View user's profile Send private message

ofer71

Global Moderator


Joined: 27 Dec 2005
Posts: 2360
Location: Israel

PostPosted: Tue Jun 12, 2007 10:37 am    Post subject:
Reply with quote

VSAM is not a database; It is an Access Method.

Do you know that DB2 keeps its data in VSAM files?

O.
Back to top
View user's profile Send private message
haidude

New User


Joined: 11 May 2007
Posts: 10
Location: Mumbai

PostPosted: Tue Jun 12, 2007 1:30 pm    Post subject:
Reply with quote

I am agree with ur post but my question is why most of the Mainfrae application contain Db2 and Vsam,is there any specific reason?
Back to top
View user's profile Send private message
expat

Global Moderator


Joined: 14 Mar 2007
Posts: 8593
Location: Back in jolly old England

PostPosted: Tue Jun 12, 2007 1:54 pm    Post subject:
Reply with quote

Quote:
VSAM is not a database; It is an Access Method.

Do you know that DB2 keeps its data in VSAM files?


Another way of putting this, is that VSAM is an access method, a way to access the data, and VSAM structured file can be used to store DB2, IMS, CICS, and more, not only DB2.
Back to top
View user's profile Send private message
mkk157

Active User


Joined: 17 May 2006
Posts: 310

PostPosted: Tue Jun 12, 2007 2:51 pm    Post subject: hi
Reply with quote

Hi Ofer71

Quote:
VSAM is not a database; It is an Access Method.

Do you know that DB2 keeps its data in VSAM files?



Expact

Quote:
Another way of putting this, is that VSAM is an access method, a way to access the data, and VSAM structured file can be used to store DB2, IMS, CICS, and more, not only DB2.



Can I know the real time exmples ot situation we use VSAM to store the data. I read this. But I never get a chance to work on VSAM till now. Please clarify my doubt.
Back to top
View user's profile Send private message
dick scherrer

Site Director


Joined: 23 Nov 2006
Posts: 19270
Location: Inside the Matrix

PostPosted: Tue Jun 12, 2007 5:39 pm    Post subject:
Reply with quote

Hello,

There are millions of VSAM files around the world that are 10 -25 years old. Actually, in many places, the vsam environment is managed as a database environment - there just is no rdbms.

Many organizations have decided to implement new systems or upgrade older systems to take advantage of database technology. Often these new/upgraded systems still need to interact with existing systems.

If is very common for an application to use both vsam and database in the same code.
Back to top
View user's profile Send private message
View previous topic :: :: View next topic  
Post new topic   Reply to topic    IBMMAINFRAMES.com Support Forums -> Mainframe Interview Questions All times are GMT + 6 Hours
Page 1 of 1

 

Search our Forum:

Similar Topics
Topic Author Forum Replies Posted
No new posts Fail to change physical VSAM filename... jacobdng CICS 6 Fri Jan 20, 2017 12:36 pm
No new posts how to recover an uncataloged VSAM da... archanamuthukrishnan All Other Mainframe Topics 3 Wed Jan 11, 2017 6:18 pm
No new posts Underlying DB2 VSAM LDS - SMF recording vasanthz All Other Mainframe Topics 6 Thu Jan 05, 2017 4:20 am
No new posts TWS EQQYCAIN - not sure how to get ap... mbenaud IBM Tools 0 Wed Dec 14, 2016 8:45 pm
No new posts BWO option in VSAM blayek CICS 3 Sat Nov 05, 2016 10:47 am


Facebook
Back to Top
 
Mainframe Wiki | Forum Rules | Bookmarks | Subscriptions | FAQ | Tutorials | Contact Us