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[Migrated content. Thread originally posted on 23 March 2005]

Again, porting from icobol (native icobol isams informix cisams) and I'm looking for some detailed technical info on the vision file system, specifically on how it treats deleted records. Delete physical doesn't seem to be an option in the select statement?

If I have a file with very high record turn over (lots of new records daily, 99.9% deleted within hours) and want to maintain a reasonably small file and index tree, am I stuck taking the file offline and sweeping it periodically?

Some isam implementations won't recycle deleted records unless you write an identical primary key, others will recycle them if you do a write and the new index would go in the same 'leaf' of a 'page' where the index for a deleted record is stored? Does anyone know how the vision file system behaves (and/or where I can find detailed technical info for vision)?

Thanks!

Steve

[Migrated content. Thread originally posted on 23 March 2005]

Again, porting from icobol (native icobol isams informix cisams) and I'm looking for some detailed technical info on the vision file system, specifically on how it treats deleted records. Delete physical doesn't seem to be an option in the select statement?

If I have a file with very high record turn over (lots of new records daily, 99.9% deleted within hours) and want to maintain a reasonably small file and index tree, am I stuck taking the file offline and sweeping it periodically?

Some isam implementations won't recycle deleted records unless you write an identical primary key, others will recycle them if you do a write and the new index would go in the same 'leaf' of a 'page' where the index for a deleted record is stored? Does anyone know how the vision file system behaves (and/or where I can find detailed technical info for vision)?

Thanks!

Steve
I'm certainly no expert on VISION details, but I can tell you that the utility "vutil" will eliminate deleted records from the file. Seems like you might need a better way. I'd be interested in hearing a better way if there is one...

Rob