| ★ APPLICATIONS ★ BUREAUTIQUE ★ MASTERFILE 8000 ★ |
MASTERFILE 8000 (8000Plus) | MASTERFILE 8000 (Aktueller Software Markt) |
SPECIAL RELATIONS Databases come and go, but Masterfile lives on. What does this latest incarnation have to offer? Masterfile 8000 is the latest version of this relational filing system, and is written especially for the PCW. It takes full advantage of the micro's best features, including the enlarged screen display, graphic capability and RAM disc. The program is completely written in machine code, which means it's fast in operation, and builds on earlier versions of the program.It started life on the Sinclair Spectrum, and progressed through the Amstrad CPC range to where it stands today. To define a file, you first enter the number of different pieces of information (the number of fields) you want to put on each record. It's important to specify a large enough number, as once you've started to define your record you can't add extra fields. This is an odd restriction, as most databases allow you to add extra fields as long as there's no data in your file. Once you've settled on the number of fields, you type a heading for each one, which may be up to 22 characters long, and specify whether the field is to contain a number, a date or simple alphabetical characters, tf you don't want to bother with other formats, that's all you need do-you can start typing in your data. You don't need to specify the length of each field, as Masterfile 8000 uses variable length records. This means that each record that is saved on disc is only the length of the data that it contains (plus a few extra bytes which the program uses to locate it). Most databases use fixed length records, which nearly always take up more room on disc, but are easier for the program to alter or delete. Drawing the line If you want to make more of the visual display of your records, though, you can define up to nine other formats. These are effectively screen layouts which may contain some or ail of the fields you defined in the base format, 0. You can specify the position of each field, give it a different title from that in the base format, and mark out a display area for the data it will contain. Each of these functions is controlled from a series of menus which appear on the screen. Although this system guides you through quite a maze of different facilities, it takes a while to get used to the techniques involved, and the menus do tend to get in the way. When you're adding headings to your layout* its a little disconcerting to discover that the cursor used for positioning them wipes out anything it passes over. This is rectified when the screen is redrawn at the end of each new addition, but if you're lining up a series of headings you have to be careful not to wipe out others by mistake. One of the powerful features of Masterfile is that the program will automatically assess the depth of the layout you produce, and display more than one record on the screen at once, if it can. In the extreme, you can have up to 28 records on the screen at once, assuming each takes up only one line of the display. Working from memory Unlike many databases, Masterfile 8000 loads the file you're working from into the memory drive before starting. This speeds up many of the programs functions, but does mean you have to remember to save your file back to disc before switching off. Masterfile reminds you to do this, but if you're the victim of a power-cut, you can lose a lot more than the last record you changed. The other disadvantage is that you're limited to the space on the M: drive, rather than the larger capacity of the A: of B: drives. To take a typical example, suppose you define a membership list, as in the illustration. There are 12 fields in the record, and you might expect the following average lengths for each:
If you allow an overhead per record of 8 bytes, plus one byte extra for each field (as suggested in the manual), this gives you a record length of 142 bytes. You should allow 2K for formats and other overheads on the disc drive, so you could expect to store 110 x 1K/142=793 records of this length on an unexpanded PCW8256, and 366 x 1K/142=2639 records on a PCW8512. If Masterfile worked with the 3" drives, though, you could have stored 1283 on the A: drive and 5177 on the B; drive. File features When you come to use your Masterfile database, you display one of the formats you've created and start typing your information into the data fields. Character and number fields accept data in any form, but date fields do some elementary checking. As long as the month isn't more than 31 days long, though, it'll probably get through. There are no calculation facilities in Masterfile, other than a simple totalling, so numbers aren't checked for size or form. When you have entered a few records, you'll probably want to browse through them. You can move forward record by record, and return to the start of the file, but oddly you can't move backwards through a fife. Records are normally displayed in the order of the field you defined as a key when you set the file up, but you can temporarily define an alternative key so that they will appear in another order. The main facilities within Masterfile are 'Find' and 'Search'. Find altows you to specify a search word in the key field, and Masterfile then hunts through the records until it finds a match. Search is rather more complex, as it allows a 'rule' to be set up, which may contain several conditions referring to a number of fields. You could, for instance, define a rule which said 'Name is Johnson, Town is Margate and Total Subs is less than £100'. All records which match that rule would then be 'selected', and only these would be displayed, until you selected the whole file again. You can define a number of different formats for the printed documents which Masterfile can produce. They are based on the screen formats, and since you can define up to nine of these, you could set up several of them specifically for printed output. Again, Masterfile will output as many records as it can per printed page. One of Campbell System's proud boasts is that Masterfile has always been a relational database, which means it can refer to data in more than one file at once, and these files can be linked by the use of common fields. This relational facility saves disc space and entry time. It won't always be of immediate use. but it's nice to know it's there if you need it. Verdict Masterfile 8000 shows its sound ancestry, being from a series of good, value for money databases. It is quick and very versatile, has plenty of scope for flexible screen and print layouts, and has good selection and sorting facilities. It's a pity there's no mathematics, though. It works fast by dealing exclusively with the PCW's RAM drive, but this does limit its capacity. If your application is large, and you own a PCW8256, you may have to think of upgrading its memory before installing Masterfile. 8000PLUS |
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