CICS VSAM Transparency for z/OS, Version 1.2


Relationship between an IRD and an FBE

There are three particular aspects to consider for IRDs:

For a multiple table solution, you write the IRD before the FBE. This reasons for this become clear as you read this section.

There is potential overlap between the functionality in an FBE and an IRD for a multiple table migration but there are two important facts to keep in mind: Because an IRD is not involved in a retrieval call, the conversion of data from its DB2 form to the equivalent VSAM form must be handled by the FBE. For update calls, conversion from VSAM form to DB2 form can be done in either the FBE or the IRD.

In general, the FBE includes SQL SELECT statements, sometimes using a cursor. The IRD includes INSERT and UPDATE SQL statements, and in some occasions SELECT statements. DELETE processing is normally achieved by DB2 referential integrity cascading deletes.



Concept topic


Last updated: December 6, 2013 20:45:2

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Timestamp icon Last updated: Friday, 6 December 2013


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