Wednesday, June 29, 2016

Easy way to initialize columns when using SQL insert

use default keyword in sql

Regular readers of this blog know that I like to keep things simple and easy. Partly for my own peace of mind, and partly if it is simple then other programmers can quickly understand what my code does. A colleague calls this the K.I.S.S. methodology, which stands for "Keep It Simple Stupid", although she often changes the last "S" to "Simon" (I am not sure what she is trying to imply by this).

A good example is when using SQL to insert a row/record into a table/file. If not all the columns/fields need to be filled I need to give them a default value. This means that I need to look at the table and determine the data type of each column and whether it can be null or not, which takes time and can leave to errors if I try and accidentally insert a columns/field with the wrong default value.

Wednesday, June 22, 2016

Write to a file in the IFS using RPG

fputs c api to help rpg write to ifs file

After writing about how to read an IFS file in a RPG program I received a message from Domenico asking me how to do the opposite.

Very interesting article, as always, the only suggestion is: since, surfing internet, it is possible to find many examples about using _c_ifs_open but not one (!!) of _c_ifs_write .. it would be very very interesting and useful for our community.

Before I get started explaining how to write to an IFS file using RPG, let me say I am not going to repeat what I said in my earlier post A better way to read a file in the IFS with RPG, so you might want to review that before continuing with this post.

Tuesday, June 21, 2016

Happy 28th birthday!

Today is the 28th anniversary of the launch of the AS400.

You can watch a video of the launch announcement here.

Tonight I will be raising a glass of my favorite beverage to wish the AS400 and its descendents, up to the IBM i, a happy birthday!

You can also learn what your PC would have been like at the time of the launch here.

And the family tree that took the AS400 and evolved to became the IBM i here.

Wednesday, June 15, 2016

Calling a program on a remote IBM i using SNADS

programming using ddmf to get data from another server

I received a question from a reader asking if there was a way to copy data from a central IBM i to a number of remote IBM i using SNADS, and then have the central server call a program on the remote ones. Fortunately this is easy to do just using a few simple commands and a bit of common sense.

Distributed Data Management (DDM) files have been available on IBM computers for as many years as I can remember. DDM files are a quick and easy way to copy data to and from one IBM computer to another. Most of my experience with them has between AS400 and later IBM i, but I have also worked receiving data from an IBM mainframe via DDM files.

Wednesday, June 8, 2016

Using SQL to update a column with the greater value of two other columns

update column with the greater value from one of two other columns

I received a call to action from my superior. "The Order Close Date in the Order History file has been messed up. Can you write a program to fix it?"

"When do you want this for?" I replied.

"Next week" he shrugged.

I have more than enough time, four days, to write a RPG program, but where is the fun in that when I could do something with SQL? Especially when this is something I have never done before: compare two values and use the greater to update another value.

Wednesday, June 1, 2016

Debugging a batch job

debugging a program that has been submitted to batch

It is a surprisingly common misconception that you cannot debug a program that runs in batch. While you have to perform some extra steps, which identify the job you want to debug within, the debugging interface is identical to that of a interactive debug.

To be able to run source debug, whether interactive or batch, you need to create (compile) your CLLE, RPGLE, and SQLRPGLE objects with the appropriate debug view parameter. To learn about the various debug views see the post Debug views finding your favorite.