Reader Feedback and Insights: No Field Reference File, No Problem

Hey, Ted:

At my company we are using SQL data-definition language (DDL) to define new databases and are supposed to be converting all tables to DDL. We have come across problems that are irritating but not insurmountable.

The biggest problem is renaming file formats in RPG IV: When a table is created with DDL, its format name is the same as the file name. We also have major problems with mirroring constraints to our other boxes. According to our mirroring software vendor, other vendors have the same restrictions because of the way IBM implements constraints in DB2/400. We have to promote the table creation DDL to the source box, and promote the constraints to the source and mirror boxes. The least of our problems is the lack of a field reference file. Many of our DDS files were created with field reference files, but the design and implementation were so poorly thought out that you can't rely on the benefits of field reference files.

I prefer table creation with SQL, but DDS has several advantages over SQL that should cause everyone to investigate the ramifications of "migrating" their databases to SQL. I hate pronouncements like, "Use SQL to create all files," "Use SQL for all I/O," or "Use Java instead of C, RPG, or COBOL." You must determine which tool is best for the job at hand. Using a hammer to cut a hole will work, but if you want it done right you will use a saw.

--Duane

One way to get around your biggest issue is to create the table with the record name, then rename it to the table name. The record format will have the original name, not the new name.

I know. It's a kludge.

--Ted

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