On 12/8/14 11:33 AM, Alan Campin wrote:
"I’ve taught RPG to many Java/C++/.Net/etc. programmers and most of them
embrace record I/O as being simpler -"
Sorry to be so long in responding to your responses to may statement
concerning SQL.
1. Concerning simpler. I just don't get that.
Are you telling me that if you told a Java Programmer that you had an I/O
method that reads the entire record into the program and that if you wanted
to make the smallest change to a table they would have to recompile every
single program in the system that used that table and index that would be
simpler?
Are you in the habit of changing the structure of files at the drop of a
hat? Because unless there's a legitimate reason for that (in which case
SQL *might* be simpler, or might *not*), your file structure must not
have been engineered right in the first place.
In the second place, Java applications tend to be composed of large
numbers of classes, usually contained within JAR files, and unless your
application is really, really small, you're typically working in an IDE
that will rebuild the whole thing, if necessary, at the click of an
icon. RPG applications tend to involve fewer distinct programs and
service programs, usually a small enough number that even a fully manual
rebuild (and it's very easy to automate a rebuild in CL) is no problem.
In the third place, what would you rather have? An application that
crashes on takeoff, relatively harmlessly, if the file structure is no
longer compatible with it, or an application that blithely corrupts an
incompatible file because SQL (much like C) will give you enough rope to
hang yourself, then help you tie the noose?
Besides which, if there's a legitimate reason to be changing the
structure of files at the drop of a hat, there are ways, involving (1)
having full control over how, when, and why the file structure is
changed, (2) opening files in program-described mode and (3) getting the
meta-data dynamically, that allow RLA to safely avoid the need to recompile.
SQL exels at things that are very difficult in RLA. RLA excels in things
that are very difficult (often involving massive, bizarre, workarounds)
in SQL.
You don't generally use a screwdriver to apply paint, and you don't
generally use a paintbrush to drive screws. The right tool for the right
job.
--
JHHL
midrange.com
