What I'm wanting to do is append multiple ISAM files together, but I'm only interested in certain fields. Together the files consist of about 10,000,000 records so I'd prefer it if I didn't have to perform a whole load of IO if possible.
I'd like the output to consist of particular fields from each ISAM, along with the directory the original ISAM came from.
Basically wondering if there's a nice little tool to use to do this quickly that doesn't use too much disk space, as that is fairly limited.
About 10 years since I did anything with ISAM files but I don't think the DCL utility 'APPEND' will be of much use because you want to select certain fields.
Perhaps C or C++ have similar file handling facilities but DEC Fortran was the language of choice (people might disagree) that 'went with' with VMS from the early days - so I'd write a Fortran Program, opening the 'INDEXED' Input files 'READONLY' and the output file with the 'APPEND' attribute, reading the input records and writing out the new data records. (the language user and reference manuals are online and there are probably some example programs)
It would probably wise to make data backups (somewhere) before starting.
Sorry to be a bit vague but I'd need try 'things' to re-familiarize.
Thank you for your reply. This project has been moved to somebody else now as I have other more urgent tasks to be getting on with; however, I will inform my colleagues of your advice. If I have any follow up questions I will be sure to return and if we happen to find a solution that I feel would be useful to anybody attempting a similar task I will post it on here.
malmberg December 12 2017 HPE only makes the most current version of OpenVMS Alpha / IA64 /VAX available to hobbyists. When I had access to the Alliance 1 program it was the same. No public downloads are allowed by HPE.
nmbonao December 08 2017 Is anybody knows OpenVMS 8.2 version downloadable version? or CD copy? Thank you very much
aarommes December 02 2017 Bitcoin and Blockchain enthusiasts ( plus distributed computing ) please connec / reply: http://www.openvmshobbyis t.com/forum/viewthread.ph p?forum_id=130&thread_id= 2991
malmberg September 10 2017 https://sourceforge.net/p /vms-ports/wiki/VMSInstal lation/ For the most part just use VMS 6.1 media instead of 7.3. But why run the older release?
DoeveR August 07 2017 Where can I find the write up on running VMS 6.1 using the simh emulator?
Bart March 20 2017 Happy to have found my password again!