APPLICATIONSDIVERS ★ SAGE DATABASE: Not hostile, but do treat with respect... ★

Sage Database (Computing With the Amstrad)Applications Divers
★ Ce texte vous est présenté dans sa version originale ★ 
 ★ This text is presented to you in its original version ★ 
 ★ Este texto se presenta en su versión original ★ 
 ★ Dieser Text wird in seiner Originalfassung präsentiert ★ 

Data management systems generally involve a trade-off — the greater the range of facilities, the more rigid and unfriendly the rules for structuring the data.

From this point of view the Sage Database is a middle of the order package, not as hostile as full-blown relational databases, but more powerful and therefore less forgiving that simple electronic card index systems.

With the Sage package the most demanding operation is that of setting up a new file, since this involves a degree of planning at odds with the way most people's minds work.

The user has to declare in advance the number of fields per record their lengths and types, output width, left or right justification, decimal precision, conversion to upper case and so on. Apart from the purely cosmetic operation of altering screen display coordinates, changing a field paramentcr in an existing file involves restructuring the entire database.

On the other hand, with a measure of forethought and almost certainly some frustrating trial and error it is possible to set up precisely tailored data-entry and report-generation procedures. 

Files and individual fields can be permanently or temporarily protected with a mixture of locks, passwords and un-echoed keystrokes, and there is total flexibility in field selection for report purposes. There is also a wide range of field types, including compacted numeric and date fields, time fields and fields on which various kinds of calculation can be carried out, with column totals and basic statistical analyses thrown in for good measure.

Data entry in selected fields can be restricted to numeric to textual ranges, such as allowing only numbers between 1 and 50, or only YES or NO. Forced entry can be specified, obliging the operator to enter information before moving to the next field.

The built-in text editor and mailshot utility are surprisingly powerful. In fact the set of page layout commands doesn't fall far short of that of many dedicated packages, and the range of options includes such things as run time keyboard input and viewing a merged letter on screen before printing. Labels can he printed using the special utility provided, though unfortunately it limits you to a three-across format.

Of course the provision of a wide range of merge-print features inevitably adds to the complexity of using the program. So again, despite Sage's praiseworthy attempt to sugar the pill, inexperienced users will probably have to learn through bitter experience.

However for those who find creating a new file or producing personalised letters a daunting prospect, interrogating a database and manipulating the information it contains is about as gentle an exercise as it could be.

In what Sage calls the Enquiry Processor, the normal computer-style database query language has been replaced by a welcome English-like syntax. This has been achieved by a judicious choice of system words and by adding a sprinkling of disposables — these are words which may be included for the sake of intelligibility but which the program will ignore. The following command, for example, would be syntactically valid:

Please list all employees with a surname of Jones and a salary greater than 6,000 showing me the age and the deépartment, Thank you.

Using field numbers instead of names, symbols instead of words and discarding disposables, this could be reduced to:

list employees with 1="Jones" and 5>6000 show 8 9

The Enquiry Processor is also used for sorting records, either relatively slowly if in-string searches or searches with relational operators have to be carried out, or rapidly if a key field consisting of only a compacted record nuir.ber has been included in the initial file definition.

Such indexed fields are a common feature of databases, and even some of the simpler ones allow a number of fields to be indexed. Surprisingly the Sage Database allows only one — the key field — which could prove something of a nuisance if your records are mostly textual, such as in a bibliography, or if you constantly require numeric sorts. Furthermore search criteria are restricted to two fields at a time and the program will only sort into ascending order.

Again however these limitations have to be set against the plain English implementations of the search and sort commands. In many circumstances speed and range may be secondary considerations when it comes to being able to give a clear instruction such as:

Sort products by category with price greater than 20 or weight less than 8 showing total number of ptr

Much of Sage's reputation for quality Amstrad applications software has been built on the fact that their products have been well implemented on the PCW and designed as far as possible to run on the entry-level system. I was therefore surprised to find that the database has not been configured with the care we have come to expect.

For instance, the Delete key does not work properly in the Enquiry Processor — Alt + H has to be used instead — and the program is not completely bomb-proof. On one occasion I managed to crash back to CP/ M, having permanently corrupted some data by trying to write to a disk previously used for PCW Locoscript files, on a single-drive PCW or CPC6128, the user must make alarmingly frequent changes between system and data disks. Sage admittedly recommends that the program should be run on a twin drive machine, but surely better use could have been made of, for example, the PCW's RAM disk.

The documentation is of a high standard, with an excellent tutorial to got you started.

However errors in the instructions for making a working program disk are hardly likely to inspire first-time users with confidence as some of the descriptions of the more advanced functions, contained only in appendices. are equally likely to baffle them.

Yet despite these criticisms — most of which are ultimately relatively minor — the Sage Database is worthy of serious consideration if you have a twin drive machine, and have not yet invested in a data storage and retrieval system. It is not an outstanding bargain, but it doe3 offer significantly more than many of its rivals in the same price bracket.

Gabriel Jacobs, CWTA

★ YEAR: 1987
★ CONFIG: 128K + CP/M
★ AUTHOR(S): ???


Je participe au site:
» Newfile(s) upload/Envoye de fichier(s)
★ AMSTRAD CPC ★ A voir aussi sur CPCrulez , les sujets suivants pourront vous intéresser...

» Applications » CP/M Lader v2 (CPC Magazin)
» Applications » CP/M Plus Patch mit dk'tronics RAM (Schneider Magazin)
» Applications » Initiation au CP/M Plus (Amstrad Cent Pour Cent)
» Applications » Camsoft Stock Control
» Applications » Basic-Lader_fur_Deutscher_zeichensatz_unter_CPM
» Applications » CPM Bootstrap Converter


L'alinéa 8 de l'article L122-5 du Code de la propriété intellectuelle explique que « Lorsque l'œuvre a été divulguée, l'auteur ne peut interdire la reproduction d'une œuvre et sa représentation effectuées à des fins de conservation ou destinées à préserver les conditions de sa consultation à des fins de recherche ou détudes privées par des particuliers, dans les locaux de l'établissement et sur des terminaux dédiés par des bibliothèques accessibles au public, par des musées ou par des services d'archives, sous réserve que ceux-ci ne recherchent aucun avantage économique ou commercial ». Pas de problème donc pour nous!

CPCrulez[Content Management System] v8.7-desktop/cache
Page créée en 307 millisecondes et consultée 854 fois

L'Amstrad CPC est une machine 8 bits à base d'un Z80 à 4MHz. Le premier de la gamme fut le CPC 464 en 1984, équipé d'un lecteur de cassettes intégré il se plaçait en concurrent  du Commodore C64 beaucoup plus compliqué à utiliser et plus cher. Ce fut un réel succès et sorti cette même années le CPC 664 équipé d'un lecteur de disquettes trois pouces intégré. Sa vie fut de courte durée puisqu'en 1985 il fut remplacé par le CPC 6128 qui était plus compact, plus soigné et surtout qui avait 128Ko de RAM au lieu de 64Ko.