[Info-vax] Example of random access by record number on an RMS fixed record size, relative organization file?
Dave Froble
davef at tsoft-inc.com
Thu Sep 21 13:23:51 EDT 2023
On 9/21/2023 1:10 PM, gah4 wrote:
> On Thursday, September 21, 2023 at 5:19:50 AM UTC-7, bill wrote:
>
> (snip)
>
>> While ISAM may be less efficient relative files can waste a
>> lot of space. Space is allocated for empty records and back
>> in the good ole days disk space was premium and very expensive.
>
> Relative files are convenient if your numbering system is already
> not sparse.
>
> Otherwise, it is usually to make it a hash table, and hash the
> index before using it to read/write a record.
If the requirement is some type of keyed file, then just use a keyed file type.
--
David Froble Tel: 724-529-0450
Dave Froble Enterprises, Inc. E-Mail: davef at tsoft-inc.com
DFE Ultralights, Inc.
170 Grimplin Road
Vanderbilt, PA 15486
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