[WEB4LIB] Databases: Access, Oracle, Sybase

Wed Jun 7 11:50:59 EDT 2000

Good questions but not easy to answer in a short space.  I can point you to
some very good resources.

Above all don't make any important decisions until you've looked at Philip
Greenspun's book.  The entire book is available at his Web site at
http://www.arsdigita.com/books/panda/.  It's a great resource with a
refreshing point-of-view and will help you think past vendor's hype, which
can be very misleading in this area.

A few caveats about Greenspun's book though:

His specific recommendations for technology (AOLServer and Oracle) are set
by the fact that he's been using them highly successfully for six years.
Take more seriously his view that you should stick with the technology you
know best.

He doesn't give much space to open source alternatives (although he does
recognize them here and there).  Databases such as MySQL and PostgreSQL are
worth checking out as are database to Web connection tools such as PHP or
Zope.  Be sure to check them out as well as the commercial products from
Allaire, Microsoft, Oracle, Sybase and their ilk.

He's a computer science professor so he's well versed in principles of
databases, so although he stresses the importance of database design he
seems to take it for granted that everyone will have an easy time designing
databases.  I think it is extremely important that you do some basic reading
in database design and fortunately there are some very good resources
available here for the layman.

For database design, I would recommend you start with John Ashenfelter's
"Choosing a Database for Your Web Site".  It includes clear answers to most
of what you've asked and starts with a basic introduction to what databases
are and how they work and how to design them.  In the design chapter he
walks you through the design of two modest databases and then uses those two
designs as examples in the later chapters where he is evaluating and
comparing various technologies.

After Ashenfelter go on to the book he recommends, Michael J. Hernandez's
"Database Design for Mere Mortals: A Hands-On Guide to Relational Database
Design".  This is another clear introduction to what can be a very esoteric
subject.

Now on to some of your specific questions:

1) Is the database that I described above an Access database?

No.  Access is a database management program that stores data in a native
file format (*.mdb).  Only such a file can be used to take advantage of all
that Access can do.  However, most database management programs can export
and import data in other file formats so that the data can be shared with
other programs.  This is essentially how you are using Access.

2) If not, how does an Access database run?  Do you need Perl or another
programming language?

An Access file (*.mdb) is accessed either by the full Access application
software or by a special piece of software called a database driver.  The
driver can allow other applications to talk directly to the mdb database
file.  For example, I created an Access database on a Win95 machine and then
moved just the file to an NT server that did not have Access installed.  It
did however have an ODBC driver for Access installed.  This was all that was
necessary for a Web script (I was actually using HTX/IDC rather than ASP)
under Microsoft Internet Information Server to get information from and
update the Access file via the Web.

3) Do you need Perl (or another programming language) to bridge between
your HTML pages and other databases such as Oracle and Sybase?

You need three things to deliver data from a database to the Web: a Web
server, a database management application, and a means of connecting them.
CGI scripts are one means of connecting them.  Perl is one (popular choice)
for a CGI scripting language but many others are possible (for example,
shell scripts, C/C++, and Python).  The future seems to lie with an
alternative to CGI scripts, an HTML templating language.  This is a language
that allows you to embed dynamic calls to applications in what is otherwise
an HTML page.  When the page is requested the embedded calls are used to
generate HTML that is sent as part of the page.  Several variations on this
idea are in available:  Microsoft's Active Server Pages, Allaire's Cold
Fusion, the open source PHP hypertext processor (http://www.php.net/ ), and
the Zope application platform (http://www.zope.org ).

Chris Gray
University of Waterloo Library

-----Original Message-----
From: web4lib at webjunction.org [mailto:web4lib at webjunction.org]On
Behalf Of Michael A. Weber
Sent: Wednesday, June 07, 2000 10:32 AM
To: Multiple recipients of list
Subject: [WEB4LIB] Databases: Access, Oracle, Sybase

Web4libers:

I getting curious about web databases.  I want to learn more about
programming Access, Oracle, Sybase, Perl, and other databases.

I am wondering:

1) What are the strengths and weaknesses of these databases?
2) Which ones are easiest to learn?
3) What online and print resources are available that will give me a
practical "dive-in, and just do it" introduction to these databases?

Right now our webhost has constructed a database that uses a Perl program
to read data from a text file.  We can update this text file using MS
Access.

However I am finding that I need to update more than just the data.  We
want to add fields to the database and/or update the functionality.  I am
also interested in constructing some new databases.  In order to do this I
would need to learn Perl.  Since this doesn't seem to be an easy task, I am
finding that I need to pay a programmer $1500 every time I make a simple
update.  This being the case, I would like to be able to make some simple
databases on my own.