Image will know that the record is possibly in memory and will do a search
for it before it does a disc read.  However your check will be much faster.
Unless there are other fields which need to be retrieved which other people
have updated your check will be the best.


-------------------------------------------------
Larry Simonsen                Phone: 801-489-2450
Flowserve Corporation     Fax: 801-491-1750
PO Box 2200                    http://www.Flowserve.com
Springville, UT 84663      e-mail: [log in to unmask]
-------------------------------------------------
All opinions expressed herein are my own and reflect, in no way, those of my
employer.

 -----Original Message-----
From:   Jim Phillips [mailto:[log in to unmask]]
Sent:   Monday, October 18, 1999 3:42 PM
To:     [log in to unmask]
Subject:        Image Optimization

Does Image optimize data access?

What I have in mind is:

I'm reading a data set of invoices that have the customer number in them.
The primary key for the invoices is invoice number, and one invoice number
pertains to only one customer number. I need to read the invoices serially
because I'm selecting by invoice date, which is not a key item.  As I'm
reading the invoices, I need to jump out to the customer data set and get
some info about the customer.  Should I code something like this:

DBGET Mode 2 Invoice

If Invoice.Cust# <> Customer.Cust# then
    DBFIND Mode 1 Customer
    DBGET Mode 5 Customer
End-If

The purpose of this code is to eliminate an unnecessary DBFIND/DBGET to the
customer data set if that customer's record is already in memory.  What I
want to know is should I code this, or does Image do something like this
already?  IOW, if I do the DBFIND/DBGET every single time, am I wasting
resources by forcing Image to re-read a record that may be in memory
already, or is Image smart enough to not do the record retrieval if the
record is already in memory?

Thanks, as always, for any assistance.

Jim Phillips                            Manager of Information Systems
E-Mail: [log in to unmask]     Therm-O-Link, Inc.
Phone: (330) 527-2124                   P. O. Box 285
  Fax: (330) 527-2123                   Garrettsville, Ohio  44231