Re: AW: Can I use DDS to create an SQL table name

On 10/26/2014 6:31 AM, Birgitta Hauser wrote:

There was an article written by Dan Cruikshank in the 2006:
Modernizing Database Access
The Madness Behind the Methods
http://www-03.ibm.com/systems/resources/systems_i_software_db2_pdf_Performan
ce_DDS_SQL.pdf

... and I'm still convinced he wrote this article because of me. We
discussed in Rochester (where I participated in writing a Redbook) about
database modernization.
First thing to convert the guys in Rochester proposed, was recreating the
physical files with DDL. In my opinion converting the file definition from
DDS to DDL without adding anything new (such as an identity column) didn't
make sense. IMHO there are much more important things to do first, for
examples moving business logic into the database by creating the appropriate
views and/or replacing native I/O with embedded SQL that use the views
mentioned before, adding check constraints ...

Yes! One reason one can not add constraints to the old database is that
the old programs do not check for I/O errors, which is how DB2 surfaces
constraint violations. So:

I do not convert from DDS to DDL if there are no bigger
enhancements, even though I use the ALTER TABLE statement
for changes (and after I always determine the DDL for
the table and store it in a source file).
I'd not convert the DDS described tables before I'll
be able to redesign my database.

Yes, yes, yes! And along with the new database comes new code to access
it. The new code is designed to handle either I/O errors (for RLA) or
to check SQLSTATE (for DML).