Scor­pio News

  

October–December 1987 – Volume 1. Issue 4.

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allows multiple ‘pages’ of up to 512 bytes at a time to be ‘attached’ to the main database without the horrendous space requirement which would be added to a database if the memo fields were included inside it.

ZAP is a nice one whilst testing and mucking about, ZAP simply empties a databas! (Not to be written in the programs!!)

The debugging s much improved, the program may be ‘SUSPENDed’ and the debug mode entered. Watch out for the difference between CANCEL and SUSPEND, SUSPEND does just that and can be RESUMEd, CANCEL will certainly stop a program but it will also lose all the variables which weren’t declared PUBLIC at the beginning. Having SUSPENDed, depending on what you turned on, it is then possible to single step through a program whilst reading the current command statment and observing its results. How I wish some other interpreters (notably BASIC) would do that.

That really sums up the changes, reading the manuals helps particularly the bits about converting from DBII, as DBIII gives a short form list of the syntax changes and the new commands.

The problem is that the short form list doesn’t tell you what the new commands do, you have to look then up in the manual, well part 1 of the two manuals actally. The rel problem with the manuals is that they’ve now got so thick (nearly 9″ of A5 pages, excluding the binders) that I think Ashton Tate have made a conscious move towards ecology and protection of trees and all that, by economising of paper. The major sections of the books are separated as one would expect, but when it comes to a blow by blow description of the commands and functions, they’ve been bolted end to end rather than a separate page (or pages) for each. Worse, the command and function names aren’t listed at the top of each page which would make the manual usable, but are printed in pale green at the start of the relevant paragraph with no indention or anything. It makes it very frustrating to find anything.

I can’t think of a good reason why it should be done this way, except perhaps that the pale green is the sort of colour that photo copiers don’t like. But then, anyone who wants a copy eight or nine hundred double sided sheets to rip of the manual must be awarded full marks for masochism.

The saving grace is that the ‘HELP’ is fairly good, and may be called up from within the program by asking:

HELP XXXX

So all you need is an idea of what it is that you want help about (and the short form list provides that) and you can ask. It usually gives a brief description, the syntax and comments on any related quirks; it also lists allied commands for possible examination as well.

DBIII+ is usable and reasonably fast, not at fast as DBIII and again not as fast as DBII (the apparent speed increase between DBII and DBIII+ is more to do with the increased speed of the computer rather than any tightening up of the program). I guess this figures, as DBIII must have an horrendous command parser to unscramble some of the command lines it is now possible to write and that must take some time to do its stuff. I’ve been using one particular dBASE compiler for the last year and very sweet it is.

DB Compilers

There are three DB compilers as far as I’m aware, Clipper, Foxbase and Quicksilver. Clipper’s the one I’ve been using and the one I know most about.

Foxbase (I’m told) produces code which runs faster than Clipper and is ‘more compatible’ with DBIII+, but bas two snags. During a recent trip to the States I had the advantage of speaking to someone who has been using both Clipper and Foxbase, and allowed me the opportunity to play around a bit. It’s immediately apparent that Foxbase produces code of amazing size, I thought Chipper’ knack of producing a 120K program just to say “Hello” was a bit much, but compared with Foxbase, Clipper is very economical with space! Typical code with Foxbase is around twice the size of code produced by Clipper, I’ve no idea why, both seem to pull in the runtime modules in total when compiling, it just happens that Foxbase’s runtimes are bigger than Clipper’s.

The second snag is licensing policy. With Clipper, once you’ve paid the loot for it, it’s yours, and any programs produced for resale don’t have any kick back to Nantucket (Clipper’s publisher). Foxbase, on the other hand demand a percentage of each program sold using their


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