What’s In A Name? – Revisited Again

(Originally posted 2019-05-27.)

It seems to be in the nature of my code development work that I revisit things over and over again. You could call it “agile”, you could call it “fragile”. 🙂 I prefer to think of it as being inspired by each fresh set of customer data.

And so it is with data set names. In What’s In A Name? – Revisited I talked about gleaning information from a data set name and using bolding to aid comprehension. This is an update to that, based on some new code.

But first a confession: I reopened this code because there was a bug in it. But while I was there I was inspired to capture another hill.[1] The very same dataset that caused my REXX to terminate with an error caused a nice piece of inspiration.

The Bad

The bug was in not recognising a Generation Data Group (GDG) data set could have “19” in its low-level qualifier. That led to misinterpreting the generation number as part of a date. (GDS low level qualifiers are of the form GnnnnVmm where the first variable part is the generation number and the second the version number – so “G1719V00” means “generation 1719, version 0”.)

That was an easy one to fix but on to the nicer part.

The Good

The data set name had “BKUP” as the last but one qualifier. This to my eyes signifies the data set is a backup for something. So I added a test to detect either “BKUP” or “BACK” in a qualifier and bold it if present.

I’ve made the code general enough so I can add further mnemonics – such as “OFFSITE” or “UNLOAD”. (In fact – since writing this post on the plane to Berlin I added full-qualifier matching for “OUT” and “NEW” as one of our job dossiers had data sets with these qualifiers.)

When I examine the data set names for one step in particular, every data set with “BKUP” as the low-level qualifier has a corresponding data set with an identical name, apart from the “BKUP” low-level qualifier being missing. The “BKUP” data set is an output data set (and I know about it because of its SMF Type 15 record). The matching data set is an input data set (and I know about it because of its SMF Type 14 record).

So I think we know what’s going on here[2]. 🙂

As I concluded in What’s In A Name? – Revisited there’s value in decoding data set names. And the more common gleanings I can do the better. This is just a nice little further step in that direction.

But I remain conscious of the possibility one could go too far, or get it wrong:

• Not every word in the English language that appears inside a data set name is significant.
• Not every significant word in a data set name is even English.

But we roll on. And no doubt the next study will bring fresh ideas for code. And that’s just the way I like it.