Data Queues are a common object type in many applications on IBM i Systems: They offer an easy way to queue up data to be read and processed. Easy to load, easy to read and an easy way to handle sequential data. The only thing that I really dont like about them is the tricky way you have to poke around in them to look at their contents. But, I found this neat article on that highlights some new IBM i *API's that change to the old way that data quees are handled... we can now retrieve data queue entries without removing them. Yay!
This allows us to peek at Data Queue contents without upseting programs that are processing the queue itself...
In the past month or so, I've received two requests related to accessing data queue (*DTAQ) information. The first request concerned finding out how many messages were currently on a *DTAQ and how long the oldest message had been on the queue. These questions, to me anyway, suggest a management application to periodically poll *DTAQs and determine whether they are backlogged and in need of additional readers to be started and/or are stuck for some reason, for instance an outstanding inquiry message.