IS-DOS - Computers are capable of storing and retrieving any information that can be presented in digital form.

 +--------------------------+        

 DATALOG FOR IS-DOS              

 +------------------+        

 Computers are capable of storing and
look for any information that may
be presented in digital form. Bases
data is a collection of facts,
statistical data and other information
in digital form, recorded on media.
 Databases are varied.  Many of
they are worn mainly
bibliographical in nature, but there is also
those that offer consumers
summary of various materials, potentially
related to the search topic. Another large
group includes databases containing
digital information, such as data
economic statistics. To the third group,
gradually increasing their share, include
databases that provide
consumer with full texts of articles,
reports and other materials. The largest
multimedia are popular
databases that include not only
textual, but also graphic, and even
audio information.                      
Connection with large databases
carried out mainly by
computer networks. But if the base is small,
then it may well fit on your
hard drive or even on a floppy disk.           
    Why you need a database is up to you.
Catalog of games collection, peripheral circuits
devices in text form or simply
English-Russian dictionary. For quick search
the necessary information you will need
special database processing program
data.   There are similar ones on Spectrum
programs.  Written in different years, with
with varying degrees of professionalism, they
quite suitable for practical
applications.                               
 If you are familiar with IS-DOS, and not
with a Datalog DBMS written for it, then
pay attention to this program. I can with
I can say with confidence that today
there is no more powerful and convenient system today
Database processing on Spectrum.
Variable internal structure, large
data processing capabilities and of course
file system of IS-DOS itself, make
Datalog is an indispensable assistant in managing
various card files and catalogues. Program
allows you to store up to 95 bases on the carrier
data including, each, 950
cards.But I won’t fully describe this
program, everything useful can be read in
description for it.                           
    Here I want to say one thing
major and annoying drawback of Datalog,
which for many years has bothered me when working with
this DBMS.                                
    In the program, as it should be in
systems of this kind, it is possible
removing unnecessary cards and subsequent
compression of data on storage media for
speed up work with them.                  
 So, an unpleasant feature
Datalog is something that is safe to compress
data is only possible if
deleted records are located only in
end of the database!                        
 After much trying, I worked out
a kind of algorithm of actions for
deleting records and then compressing them
data.                                   
    1.  Enter into the sort field
intended for deleting records,
symbol "I".                               
    2.  Sort records by
increasing.                              
    3. Order the data. 4.  Delete those now at the end
records.                                   
    5.  Compress data.  Just like this
Makar and you can condense the data into
Datalog, unless of course you get into the code.   

    But the program is still useful.