A word that sometimes strikes fear into the programmers, "recursion" is sometimes the only tool for the job, and this article shows you how to recurse in SQL.
Written by Joe Pluta
Today's article is very simple and straightforward. I'm going to present you with one of the more complex basic SQL statements you'll run across and then break it down piece by piece. I know that the "complex basic" seems somewhat paradoxical, but it's not. The SQL statement I'll be showing you is basic because it has no frills; pretty much everything in the statement is needed to do what we need to do. At the same time, the statement is complex because even at its minimum the statement requires a lot of moving parts. Fear not, gentle reader, I shall act as your guide through this dangerous territory, and at the end, you'll have yet one more powerful weapon in your programming arsenal.
Learn how to write an inquiry-handling exit program.
Written by Bruce Vining
This is the third in a series of articles related to inquiry messages. The first two articles, "Beyond Watches" and "Validating Inquiry Message Responses," introduced the use of the reply-handling exit point QIBM_QMH_REPLY_INQ. With this exit point, you are able to validate the reply and, if you want, change the reply after the end user responds to an inquiry message. The current article introduces another exit point in the system. This exit point, QIBM_QMH_HDL_INQEXT, allows you to intercept an inquiry message before the end user is involved. That is, your exit program can directly provide the appropriate response without any operator involvement.