RE: 4 - subfiles

Is there any chance of getting the "shell sort" code for re-sorting a
subfile.  I have heard that it can be done but have never seen any examples.
 
Much appreciated,
 
Christopher K. Bipes     mailto:ChrisB@Cross-Check.com
<mailto:ChrisB@Cross-Check.com>  
Sr. Programmer/Analyst   mailto:Chris_Bipes@Yahoo.com
<mailto:Chris_Bipes@Yahoo.com>  
CrossCheck, Inc.         http://www.cross-check.com
<http://www.cross-check.com/>  
6119 State Farm Drive    Phone: 707 586-0551 x 1102 
Rohnert Park CA  94928 Fax: 707 586-1884 

*Note to Recruiters 
Neither I, nor anyone that I know of, is interested in any new and/or
exciting positions. Please do not contact me. 

-----Original Message-----
From: John Taylor [mailto:john.taylor@telusplanet.net]
Sent: Thursday, November 04, 1999 3:06 PM
To: MIDRANGE-L@midrange.com
Subject: Re: 4 - subfiles


Booth,
 
If you're really concerned about the read performance, you could simply
define three additional subfiles. Load the first (default) when the pgm
starts, then switch the subfile you're displaying based on the user's
selection. If the user selects a view that hasn't been initialized yet, go
out and do the read at that time, otherwise just keep alternating the sfile
that is displayed.
 
Another alternative, and one that I have used a few times in the past, is to
only use a single input file regardless of the number of logical views that
the user can choose from. The initial subfile load is performed using the
default sort order. When the user requests a sort on a specific column, I
just perform a standard shell sort right in the program.
 
For what it's worth, I don't think that you are dealing with enough records
for it to really be much of an issue which method you choose.
 
Regards,
 
John Taylor
 
 
----- Original Message ----- 

From: boothm@earth.goddard.edu <mailto:boothm@earth.goddard.edu>  
To: midrange-l@midrange.com <mailto:midrange-l@midrange.com>  
Sent: Wednesday, November 03, 1999 19:08
Subject: 4 - subfiles


Here's a subfile question.  I'm not very good with them.  I have a display
screen showing a subfile with 4 fields.  Each field is the key to a logical
file so there are 4 logical files in the F-specs.  For clarity, lets call
the fields LastName, FirstName, ExtNbr, DeptName.  I want the user to be
able to display any one of the 4 logical files.  I know the file will never
grow beyond 999 because the ExtNbr field is 3/0, and because there's only
about 150 extensions now, anyway.   Every time the user selects another
logical to display I clear the subfile and  reload the entire file to the
subfile.  With a dozen test records I'm getting sub-second reloads.  Now, as
the number of records increases it seems to me that reload times will
increase.  Still, I know that 5000 records load in 11 or 12 seconds so the
time for about 200 records will probably be a second or two. 

However, it occurs to me that having loaded the subfile, I shouldn't need to
read the data file again.  I am thinking there must be an easy way to save
the subfile in case it is needed again, instead of just clearing it, or am I
tilting at windmills?

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