AW: Variable length fields

Hi,

just a thougth: Did you make sure to fill your data fields always with
%TRIMR in order to cut the trailling blanks?

Regards,
Werner Noll

-----Ursprüngliche Nachricht-----
Von: d.bocian@xxxxxxxxxxx [mailto:d.bocian@xxxxxxxxxxx]
Gesendet: Mittwoch, 30. Juni 2004 23:43
An: midrange-l@xxxxxxxxxxxx
Betreff: Variable length fields


Hi.  We are trying to use variable length fields in a file, but so far there
doesn't seem to be any advantage to them.

As a proof-of-concept, we created a file with eight fields, all variable
length.  We set the maximum field sizes at 10 bytes, 20, 30, 40, etc.  After
compiling the file, we added three records.  The record length was 376
bytes; the total size of the file was 32768 bytes.  The two-byte length at
the beginning of each field was correct for the data in that field, so
everything seemed okay.

We then created a fixed-length file.  It had the same eight fields, with the
same lengths (leaving off the VARLEN keyword, obviously).  The same three
records were added to this file after it was compiled.  This time, the
record size was 360 bytes and the total size of the file was 24576 bytes.

That did not match what we were expecting to see at all.  We thought that
using variable length fields would take up only as much storage as they
really need.  Why then would a variable length file be *longer* than a fixed
length file.

(I should mention that none of the data in the fields came anywhere close to
the maximum size of that field.  Had we filled the fields to their maximum,
then I would expect the variable length file to be larger than its fixed
length counterpart, owing to the presence of the length bytes.)

Just for the fun of it, we created another variable length file, this time
specifying VARLEN(10) on each field.  We thought that *maybe* the absence of
an allocation length was causing these odd results.  But in the end, it was
the same result:  a 376 byte record with a 32768 byte file.

We looked to see if there was a keyword on the compile that we were missing,
but that doesn't seem to be the case.

Does anyone else use variable length fields?  Is this normal, that a var-len
file should be larger than a fix-len file?  Is there something we are
missing?  Any help or information would be appreciated, because if we're
doing this properly, then there doesn't seem to be any value to
variable-length fields.

Thanks.

David Bocian
--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/midrange-l.