Since writing to a data queue and reading from it are supposed to be complimentary things, I could not wait to complete this article.

In the previous example, we wrote (sent) some values to the data queue. To verify that those values were indeed written to the data queue, we are using another API QRCVDTAQ we discussed in the earlier blog.

Okay, so far we’ve learnt the basics. Now here’s an example which will clarify the things. In this example, we are sending some entry to the data queue using a data structure.

Why Data Structure?
Data structure makes it easier to send multiple types of data at a time to a data queue. In this example we are trying to send an alphanumeric and numeric data type values to the data queue. However, do remember that everything is passed as a character field only.

Required Vs. Optional Parms

Data queue can be divided into three types based on how they allow you to retrieve individual records. They are

1. LIFO Type Data Queue :- In such type of data queues, the last entry to data queue is the first one which is sent out of the queue. Consider this example to be similar to books stacked up in a cubicle box. The last book entering the box is the once which is removed first.
   

What is an AS400 Data Queue:-
An AS400 data queue is just what it says; it is a sort of queue ;-), a physical one. Data waiting to be picked for processing is lined up in this queue. Once a data record is picked up (by reading the data queue), that record is removed automatically from the queue.

Data Queue and Physical File

Okay, Several times, we need to convert capital letters of a word or an alphanumeric characters to small letters. One practical example which I can think of now is when we receive some input in the form of a flat file. While validating input fields from the flat file, say the Name, we should convert them to all small or all capital before comparing with the system value. Here's a quick and easy way to do the conversion.

The Formula:-

We can capitalize all letters of a particular character variable, using the RPG 400 built in function %XLate.

Source Entry utility does not allow to add more than 32764 records at a time. This is the limitation with SEU. However, AS400 does allow more records to be added to the program source.

This usually is done programatically. Famous tool SYNON is notorious to add frequently more than 32764 records.

If we try to view such source by taking browse option, the error "Member MbrName in file Library/QRPGLESRC exceeds 32764 records." is thrown
by the SEU.

Question is how to view the source generated?

To browse such source,

After several months, I am back with a new post. I was not getting too much time to update the website. I hope you have liked this website so far. Thanks for your support.

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