[Info-vax] Indexed RMS file question

[Jeffrey H. Coffield]

J Xenu wrote:

> Alpha  1-18   data
> Alpha  19-72  more data
> Beta   1-10   bla bla
> Beta   11     more stuff
> Beta   12-32  even more data
> Beta   33-50  This is the data I want
> Beta   68-100 xxx
> Gamma  1      yyy
> Gamma  2-140  zzz
> 
> Assume I do a read with Key 1 = "Beta" and Key 3 = 42. I want the read to
> return the record with data = "This is the data I want" since key 1 matches
> and Key 3 falls within the range 33-50. How do I define the keys, especially
> Key 3 without creating a duplicate record for each possible key3 value?
> The ranges are pseudo-random, not multiples of anything. There can be gaps as
> well, (for example "Beta", 62 in the example)

If you assume that the ranges do not overlap then one approach would be
to create two fields. The first with the Alpha/Beta/Gamma data, the
second with a zero filled string as the end of the range. Make this a
segmented key and then you can do a read key less than or equal to your
Beta, 00062 and get the record you want.

To help more, I would need to know more about the application and what
language you are using.

Jeff Coffield
http://www.digitalsynergyinc.com