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into The Archive
The QL's flexible database: by David
Nowotnik
Of the four software packages
to be supplied free with the QL,
the database program, 'Archive'
could well be the one most widely
used. For while the QL rests in
the precarious no-man's-land at
the top end of the home computer
market, and bottom of the
cut throat business arena, infor
mation storage and retrieval will
be the major link between the
wide ranging band of QL users.
Whether one examines the
original versions of 'Archive',
supplied to all buyers of the QL
prior to February '85, or the
upgraded and improved 'V2 .0',
the overall conclusion is the
same. 'Archive' can provide a
superb database system. Its
great strength is that it can be
tailored exactly to meet the
user's requirements; none of the
compromises that accompany
those ill-fitting, off-the-peg
packages are necessary.
Archive's strength,
however, is also its weakness.
When loading Archive into your
QL, you haven't got a working
database, though you do have
the means to create the
database. Archive is a high level
programming language, not too
dissimilar from SuperBasic,
which allows a database suite to
be created. High level commands,
such as 'Create', 'Insert',
and 'Find' perform the majority
of conventional database
operations, but it is still left to
the user to put together to
program — his/her lists of commands
to create the required application
for Archive.
Particularly in the business
area, users might well be unable,
or unwilling (for reasons of time)
to develop their own suite of
procedures which provide the
basis of any database application
program. Fortunately, there
is no copyright restriction on individuals
or software houses
creating for sale database application
software written in
Archive's programming
language, for use with Archive,
While neither Sinclair Research
nor Psion have any immediate
plans to market Archive application
programs, freedom from
copyright limitations has allowed
other software houses to produce
packages (for example,
Eidersoft sell a suite of 5
packages for £14.95). In fact,
Psion have gone a step further to
encourage application software.
They have available for
sale to individuals or companies
a 'run-time' version of Archive.
This program allows copy pro
tection of Archive application
software, making Archive a very
attractive basis for companies
wishing to develop and sell
database systems for the QL. In
the run time version, the ap
plication loads immediately (no
need to load Archive, then load
the application). There is more
RAM available for files, and
there should be extra features
not available to the standard
version of Archive.
By buying one of these
application packages, the user
is, of course, restricting himself
toan 'off-the-shelf' system, and
so cannot fully benefit from the
flexibility which is Archive's
main strength. There is the op
tion, for those unwilling to program
Archive for themselves to
pay a programmer to write soft
ware for them. But there is much
to be said for trying to write your
own software. The Archive pro
gramming language is much
easier to use than BASIC, and
the concepts of the language are
adequately covered in the QL's
User Guide, as well as a number
of other books. The Sunshine
Publication by Alison McCallum-
Varey called 'Quill, Easel, Archive
and Abacus on the Sinclair
QL' is one good example of a
text book which covers Archive
programming in an easy to
follow manner.
Your own database
If you are still not convinced that
you could write your own
database program, then read on.
Wriiing computer programs,
even in Archive's simplified pro
gramming language, is a matter
of applying logic and common
sense to solve a problem.
Reasonably, assuming that
everyone is blessed with some
abilities to think logically and use
common sense, programming
Archive should be within
anyone's capabilities.
Setting up a database
system should involve a preset
sequence of tasks; defining
exactly what is required, planning
a logical sequence of opera-
Figure 1: Schematic layout of the address program
tions to meet the objectives,
then writing procedures which
carry out these operations. The
procedures are tested individually
(to iron out bugs),
then a linking procedure written
to pull together the whole se
quence.
To demonstrate Archive's
simplicity, here is a simple
database application, a name
and address file. The list of procedures
which make up this file
is shown in fig.2 . But what may
be more relevant to the budding
programmer are the processes
which were involved in designing
the system.
When analysing any potential
computer application, the
first question that must always
be asked is 'do I really need a
computer to do this?'. In the
case of a name and address file,
if all that is required is to look up
an address or telephone
number, using an address book
will always be much simpler
funless the names exceed
several thousand!). One
justification for a computer file is
the need to sort the records in
more than one way. I find that I
have a remarkable ability for
forgetting birthdays, with the
result that family and friends are
often left disappointed. So this
name and address file includes
the ability to sort through the
records, and identify those
families in which a birthday is
imminent. The records in the file
are in no particular order (but this
could be achieved with simple
modification using Archive's
78 ZX COMPUTING DECEMBER/JANUARY 1985