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1986-09-18
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dBMAN Tutorials
#1 in a Series
General/Bug Report
by John C. Leon
August 20, 1986
distributed through the H.A.S.T.E. BBS
Houston Atari ST Enthusiasts 713-955-9532
permission granted to distribute unaltered original text
There are precious few serious databases on the market at
present for the Atari ST. The majors are dBMAN, the Manager, and
Zoomracks. H&D Base is a dead horse, as Mirage has appparently
gone out of business. Others will come. This series of
articles concentrates on what appears to this writer to be the
single most versatile and powerful program, dBMAN by Versasoft
(versions 2.00L and 2.02L are included in all remarks, with
known differences pointed out). We assume you have a working
knowledge of relational databases, and have made some effort to
use the product. For those who have never used a dBMAN or dBASE
type of command-driven relational database, I urge you to buy a
book or two on dBASE programming before tackling any heavy-duty
work with dBMAN. The two products are very similar, but far
from directly compatible, despite consistent claims by reviewers
and any ads you may see. Compatibility between dBMAN and dBASE
extends only to the ability to use the CONVERT command in dBMAN
to convert a dBASE data file to dBMAN format.
Command files (programs) written in dBASE will not run in
dBMAN without modification. The syntax of the two languages is
different, and there exist commands in each language that do not
exist in the other. Suffice it to say that the commands are
similar enough to make the porting of programs relatively easy.
The dBMAN documentation is pretty stiff. It is packaged in an
attractive slipcase and three-ring binder, containing logical
sections: basic, advance, reference, commands, functions,
appendices and index. However, the level of detail leaves a lot
to be desired. You are often merely presented a brief
description of a command or function with no explanation of its
power or usefulness. The SET RELATION TO command is incredibly
powerful, but it receives the briefest of treatment (two pages -
long by Versasoft's standards!) and no hint is given on when it
would be useful. Versasoft seems to assume that users of the
product already have a great deal of savvy on power programming
of relational databases. I would define their entire manual as
a technical reference piece.
dBMAN Tutorials - 1 - General/Bug Report
BUG REPORTS
1. The main dBMAN screen display is unstable, but this does not
appear to affect its performance. The status line (the one that
appears in inverse video), is prone to self-destruct,
disappearing in whole or in part without any reason I can find.
Printing a report causes the same few garbage characters to
appear in the left section of the status line every time without
exception. If these kinds of obvious problems exist in
something as basic as displaying a screen, what other bugs might
there be?
2. The Report Generator
2.1. The first screen of the report generator indicates
that you can use the PgDn keys (CTRL-D) to move between
screens. You are also told that CTRL-D is used to delete a
field you no longer want in the report. Wrong. It's
CTRL-E that erases a field. Version 2.02L's report
generator does specify use of CTRL-E.
2.2. I discovered a problem in changing report formats
with the MODIFY REPORT command. As you modify the format,
you naturally see your keystrokes reflected onscreen.
However, if you then save your changes with CTRL-S and
immediately try to print your modified report, you may find
that you get the OLD report format!! I have found that
after modifying a report, you must exit dBMAN to the
desktop and reboot the program before report modifications
"take".
2.3. If you specify a footer in your report, you will find
that your footer string will always butt up against the
last line of detail on each page of a report. In other
words, there is no blank line between the body of your
report and a page footer. There is a way to work around
this problem (see dBMAN Tutorial #2).
2.4. On the screen where you specify any groupings
desired, you are asked if you want a page eject after each
group. Regardless of what you specify, you will NOT get a
page eject. To get a page eject, you must not only answer
yes, but must have a group footer! If you don't want a
group footer, specify a group footer string of ' ' (a blank
space in single or double quotes). This is sufficient to
give the program what it needs to give you a page eject - a
group footer of some kind.
3. Procedures
3.1. Version 2.00L (the original ST version) can refuse to
acknowledge your procedures if you have them in folders, or
on a drive other than the drive you booted from, even if
dBMAN Tutorials - 2 - General/Bug Report
you have used the SET DEFAULT TO command to reset a default
drive and directory. What happens is that the SET
PROCEDURE TO command does not preface your procedure's file
name with the default drive and path. Version 2.02L
(available for $10 plus your original disk) fixes this.
3.2. Be extremely careful in your choice of a text editor
to use in writing your command files. All of my programs
created with the Final Word worked perfectly, until I began
to use procedures. Apparently the SET PROCEDURE TO command
forces a search of your entire procedure file, so that
dBMAN can set up its internal procedure table. If you have
any non-ASCII characters in the procedure file, dBMAN will
promptly dump you to the desktop. I've learned that Final
Word puts a non-ASCII character as the very last byte in
the file. That one odd end-of-file byte is sufficient to
kill your program entirely. I now use another editor.
As additional bugs become known, we will inform you in
separate articles. Let us know of any problems you have
experienced. We will investigate them and advise other members
and potential purchasers. I wrote to Versasoft on behalf of the
club on July 22, 1986, requesting information on our ability to
update to version 2.02L, and requesting any additional
information on known bugs and workarounds. After all, their own
manual suggests that if users have problems they should contact
their dealer or local user group. This is a self-serving
statement at best, but we do not object as long as the company
shows us some consideration by supporting the group. As of this
date we have not received a response.
SUPPORT
In this writer's opinion, Versasoft's support is good. My
several calls were always returned. I got help with several
troublesome problems I had. The third time I called I was
politely asked to send in $25 for support (they keep track!),
but they did answer my question. When I first asked about an
update policy for holders of version 2.00L, I was told there was
none. Version 2.02L only had internal program changes. A few
days later I was told by the same person that I could get an
update for $10, and that some problems with the SET PROCEDURE TO
command were cured. Get the update. It's well worth it, as the
SET PROCEDURE TO command is very important, and in Versasoft's
own words, is "all screwed up" in version 2.00L.
Versasoft's current address and phone numbers are:
4340 Almaden Expressway #250
San Jose, CA 95118
general phone 408-723-9044
dBMAN Tutorials - 3 - General/Bug Report
support phone 408-723-8384
As of July 1, 1986, Atari has the marketing rights to dBMAN.
Versasoft is still the developer and source for support. The
dBMAN runtime package remains available direct from Versasoft
for $149.95.
This series of articles is anticipated to constitute
H.A.S.T.E.'s primary avenue of support for local dBMAN users.
Many topics will be covered. We will not hold your hand,
though, so please invest some time in learning the product - we
can't teach you to read the manual (life's tough!). What you
WILL get is a high level of responsiveness to particular
problems, comments on functions and how to use them, expanded
narrative on key concepts of database design, etc.
The next tutorial will cover the report generator.
dBMAN Tutorials - 4 - General/Bug Report
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