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ODBC/32 speeds
client- server connections Native access for IMAGE, KSAM and MPE
comes with good speed, fast setup.
Review by Shawn
GordonDo you want to be able to build
client-server applications quickly? Not only build them quickly, but have them execute
quickly? If so, then ODBC/32 is for you. What ODBC/32 does is give you native access to
the IMAGE part of IMAGE/SQL, as well as KSAM and MPE files as ODBC data sources. Unlike
some other ODBC solutions available for the HP 3000, ODBC/32 doesn’t make you
configure any Allbase tables to present the views of the IMAGE/SQL database.
How does it work?
The Minisoft ODBC driver works like pretty much any other
ODBC driver on your PC. You go into the Control Panel and define a data source using the
ODBC/32 driver (See Figure 1). All of your connection
information is defined here so that your application doesn’t have to worry about it.
The ODBC/32 driver knows how to read all the IMAGE information directly, so in your
program you will get a pick list of sets and items.
Figure 2
shows an example of
this working with Fujitsu’s PowerCobol (covered in Inside COBOL this month).
If the database is not defined nicely – in other
words, using generic buffers that are defined in copylibs or dictionaries – then you
have to spend a little time in the Schema Editor to define it, just as you would for the
MPE or KSAM files. See Figure 3 for an example of the the
Schema Editor’s interface.
Features
Once you have set up your HP 3000-based data source and
configured a schema file for it if you need to, you are able to use it from any tested
ODBC-compliant Windows program. If a schema file is defined for a data source, then you
need to specify it in the ODBC configuration program. That way the defined data source is
presented to you when you access it.
ODBC/32 fully supports the HP 3000 TPI (Third Party
Indexing) Interface, as well as the recently-released IMAGE b-trees, and it appears to be
nicely optimized to take advantage of them. You also get to deal directly with KSAM and
MPE files as though they were databases. ODBC/32 will make use of the the KSAM keys if it
can – but an MPE file will, of course, always be a serial read, because there is no
key structure to it.
Installation and Documentation
You can either download the demo from the web, have
Minisoft e-mail it to you, or have them send you an actual set of diskettes and tape. The
installation is in two parts. First you have to install the server software on the HP side
and launch the background listener job. The second part is installing the ODBC driver on
each PC client. Fortunately, Minisoft sells its software as server-based, so you can make
as many copies of the client software as you want.
The documentation is very clear and concise, with plenty of
examples using various tools such as Crystal Reports, Visual Basic, InQuizitive and
PowerBuilder to name a few. I had no trouble installing, configuring and using the driver.
You shouldn’t either.
The TestDrive
This was really kind of fun to test. I spent a total of one
hour installing the ODBC/32 driver, installing Fujitsu’s PowerCobol, and writing my
first PowerCobol program using an HP 3000-based data source through the driver. I then
used my little client program to populate the data set with all the information. I tried
it with some other products as well, such as Clarion, VB, Delphi and Crystal Reports.
Crystal Reports was also a piece of cake. It took about
three minutes to create a default report against my IMAGE-based data. For some reason VB
and Delphi make the process rather complex, but I was able to easily retrieve the database
structural information in the Delphi Database Explorer.
Conclusions
The performance of ODBC/32 is nothing short of amazing. I
was able to read, delete, and update pretty much instantly. For a database that is nicely
defined it takes only a minute to set it up for ODBC access.
I have several items I would like to see added to the
product to really round it out. One is the ability to configure a security matrix for what
and how data can be accessed. It is quite likely that you would want to distribute the
same program to multiple people who had their update access disabled. You could control
this in the program, but I would have liked to have seen an external access control
mechanism.
Another area would be a debug/trace facility that would
allow you to see what kind of SQL statements are getting generated and their equivalent
IMAGE calls. I can see how this would help you fine tune your application, otherwise
it’s sort of a black box thing. To be fair, I haven’t seen any other ODBC driver
include this either.
The only other caution I would pass along – and I
believe this is true of any ODBC driver – is that this is a data access control
method, period. You can’t access custom servers, or the CI at all. If you want to do
that, then you should look at the MiddleMan product from Minisoft instead.
By the time you read this Minisoft should have released
support for reading the definition from a Quiz sub-file, and possibly support a PowerHouse
Dictionary file. ODBC/32 is a very nice solution, and much easier to work with than the
HP-supplied ODBCLink SE solution. If you are giving any thought at all about maybe letting
your users create their own reports, then pull down a demo from the Minisoft
Web site, and
get a copy of Crystal Reports and go.
Shawn Gordon, whose S.M. Gordon & Associates firm supplies HP 3000 utilities, has
worked with 3000s since 1983.
Copyright 1998, The 3000 NewsWire. All rights reserved.
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