dBase is not so much a database program as a database programming tool. On running the program disc a full stop appears on the left of the screen; this is the prompt and you create, manipulate and print out your data via various commands, which, just like BASIC or any other programming system, you can combine into programs and save for re-use. For example, the command . create zap will set up a fife called ZAP, and cue in the usual prompt questions about number and size of fields. You can immediately start entering data if you wish, but to add to an existing file you would enter the command .use zap and then .append; .edit wiH allow you to correct mistakes or update entries, though you have many advanced facilities which allow you to amend a batch of records by a single command instead of laboriously amending each one as in normal packages. Nice to be able to change "Windscale" to “Sellafield", for example, in 4,719 records at once instead of doing them all individually! At your command Now suppose you want to send a catalogue of the 1988 titles coming out on dwyle flonking to members of your book club who might be interested enough to buy. You may decide to list out just the names and addresses, in name order, of all members of your book club who have spent over fifty pounds with you, live in London, and have ordered books on dwyle flonking. You can do this at a stroke by entering first , use books index nameind and then .LIST NAME, ADDRESS FOR ORDERS>50 .AND.
"LONDON"$ADDRESS .AND. "DWYLE"$BOOKS .OR. "FLONK"$BOOKS.Although this seems longwinded, you can store it in a file (perhaps called MAILSHOT.CMD) and repeat the mailshot at any time by typing .DO MAILSHOT - ie. rerun the commands stored in MAILSHOT.CMD.Most databases can handle elementary calculations; dBase can do very sophisticated counting and totalling. You can sum over any field or part of a field of your records, store and re-use the information later. All this can be printed out, of course, with plenty of format control. Amendina the structure of a database (addina extra fields, changing the layout significantly etc) is something many large-scale users would have to do from time to time, and this can be done in seconds on dBase. On most cheaper packages it is virtually impossible. dBase is a relational database, and you can work with two database files open at the same time. This has many powerful applications as outlined previously. The range of functions in dBase is unequalled by any conventional package. The ability to write your own programs means you can prepare powerful procedures which are easy enough to be used by complete novices (not all shop assistants are mad keen on taking courses in using databases). The language is logical and simple - if you can write a BASIC listing to add two numbers together dBase will be easy - and the manual, if a little daunting, is pretty good. The only drawback, of course, is that you have to be prepared to put the time and effort in to develop your programming proficiency. 8000Plus |
