Comments on: As400 files – a basic question from a newbie

By: cindyb

cindyb — Wed, 27 Sep 2006 08:32:01 +0000

A couple of things I didn’t see in response to your question. One thing, if you aren’t aware of it is that in order to allow multiple members of a file you need to set the Maximum Members (MAXMBRS) parameter to either a number or *NOMAX. The default for MAXMBRS is 1.

One reason we use multiple members of a file is for a work file. We have an application that is used for multiple reasons. Many times jobs are run concurrently putting data into different members. After the final set of data is in a member and a report or file is created, the data is saved to tape in case the user needs to use it again or has questions about the data. When the file is backed up to tape, the member and member description is cleared. Each time a member will be used a description is put on the member so that others know it’s being used and will find a member without a description.

Hope that helps as well.

By: luishernandez

luishernandez — Tue, 26 Sep 2006 22:51:09 +0000

Something else. You could considerer using members if you need to save the data before and after some process run.

You will have only one file (filename) but it will have many members and each one probably will have different data with the same structure (it is the more common approach). You access the member?s data coding ‘filename(membername)’.

How was mentioned before, you need to be careful with logical file; understand what will happen if you use only the filename (without the membername), how you will code it in one CL to override or select the right member name (some rules about how you built the `membername? could be necessary), and so on.

Regards

By: riredcheryl

riredcheryl — Tue, 26 Sep 2006 09:33:45 +0000

Month end or year end processing for various applications is an example of when it is beneficial to use multiple members in one file. We commonly save the current month end data to member using the datestamp or other convention, prior to clearing the *first member for use in accumulating data for the new month or year.

By: bamaro70

bamaro70 — Mon, 25 Sep 2006 08:42:53 +0000

The file member is where the data is actually stored. By default, all data files have a default member (*First) that has the same name as the file itself. If you need, you can then add additional members to the file which can be processed separately from other members. For example you may have a Sales file but then have separate members for individual days.

By: wickedwoman

wickedwoman — Mon, 25 Sep 2006 08:37:46 +0000

Astradyne has pretty well nailed the answer but I thought I’d add a little more info. When a file has multiple members each physical file member must be addressed separately. However, logicals can be built over the file that include some or all of the members to allow them to be handled as one file.