RE: Road Map to move a home grown application from RPG to DB2 SQL or to any other data base platform

I don't think anyone realistically thinks you're going to put all of your business logic in your DB. My interpretation is that anything that can be enforced in the DB (via constraints or such) should be in the DB.



-----Original Message-----
From: D*B [mailto:dieter.bender@xxxxxxxxxxxx]
Sent: Friday, January 13, 2017 2:02 AM
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxx>
Subject: Re: Road Map to move a home grown application from RPG to DB2 SQL or to any other data base platform

RPG would be my preference on IBM i. But what if your DBMS is Oracle
or MS SQL Server? Developers might use SQL stored procedures, which do
run in the same address space as the DBMS although my point about
"direct access" is debatable. I'm not sure if Oracle and MS SQL Server
provide RLA in addition to SQL.

.. what you are naming direct access is ISAM and was developed in the 1960s, before relational DBMS came up. DB2/400 is the only DB2 dialect providing ISAM, IBM Host (/360, /370, z-series) has ISAM and VSAM for this, DB2 is only accessable by SQL. Unix has Informix and C-ISAM. Good practice is to use ISAM only for small Tables for large Tables and high transaction throughput RDBMS and SQL is faster and scales better.

@business logic - business rules: maybe my knowledge of enhlish language is not good enough, in my understanding business logic implements the business rules (what else should it do?)

D*B