Increased performance from dBase IV

products Increased performance from dBase IV DBase IV data management software has succeeded dBase III Plus. Designed for both OS/2 and MS/ DOS-based PCs, dBase IV includes enhancements to the dBase programming language, integration of IBM SAA-compatible structured query language (SQL) and an improved user interface. Compared with the first version of dBase which had 123 commands and functions, this version has 373 and 400 000 lines of code. A developer's edition and LAN pack are also available. DBase IV has an automatic program compiler which gives ten times the performance of dBase III Plus, according to the developer. Most single user dBase III Plus and IV programs can run in multiuser mode without program modifications. A control centre replaces the dBase assistant interface and enables users to perform data entry, query and report generation using forms and tables, without writing programs. There are six onscreen graphic panels. Each panel gives menudriven access to file management, database queries, forms creation, report generation, label design and a complete applications generator. A database can be designed from the control centre by first identifying the specific fields, specifying the amount of space for each field and naming the fields. The 'dot prompt' command interface is still supported. A forms manager allows the user to visually lay out on screen forms for data entry, modification or viewing. The report writer incorporates a 'band' concept allowing users to define groups of data and generate reports. The query design system features query-by-example (QBE) which relates data from two or more

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Software design in realtime Engineers developing realtime com-

databases when one data entry is made. IBM's structured query language (SQL) has been integrated into the dBase programming language to create dBase IV's language called dBase/SQL. Users can therefore create, modify and query databases using SQL commands or dBase commands. The applications generator automatically generates dBase IV code. It manipulates 'objects' which are defined as menus, lists and batch processes. Once users decide which objects an application will feature, they can create and position menus and lists in a WYSIWYG environment. A template language which is used to process objects before dBase code is generated is connected to the applications generator. In single-user mode, dBase IV requires an IBM PC AT, XT convertible or 100% compatible systems. It requires either OS/2 1.0 or PC/DOS version 2.x or higher. Network systems need PC/DOS 3.x or higher. Minimum memory configuration is 640kbyte under DOS and 2Mbyte total memory for OS/2 protected mode. DBase IV is available now and costs £595. The developer's edition and five-user LAN pack costs £895 each. (Ashton-Tate UK Ltd,

puter systems can use Prosa, a computer-aided software development tool from a UK company, Cocad. Prosa produces knowledge base in PROLO6format and provides structured analysis of a program while in development. Sections of software can therefore be designed and tested before the program is completed. Software is developed using data flow diagrams, state transition diagrams and entity relationship diagrams drawn on the screen. Userdefined objects are described in the system's data dictionary. As realtime characteristics are an extension of standard structured analysis methods, the tool can also be used in the analysis and specification of c o n v e n t i o n a l d a t a processing systems. Prosa operates on IBM PC AT and compatibles with 512kbyte of memory, enhanced graphics adapter (EGA) graphics (128kbyte) and two RS-232 ports. Prosa costs £2750. It is available worldwide. (Cocad Ltd, Ashford

Oaklands, 1 Bath Rd, Maidenhead, Berks SL6 4UH, UK. Tel: (0628) 33123) []

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Hewlett-Packard adopts Unix

interface will be provided through which MS/DOS and OS/2 systems will be able to run Unix system applications. Third, the NewWave environment will be ported to HPUX and made available on Unix workstations. Office services to be ported to HP-UX include communications software for electronic mail, document conversion and the electronic exchange of documents. (Hewlett~

Hewlett-Packard will make its key office system products available under the Unix operating system. Development will occur in three parallel phases. First, office and communication services will be ported to HP-UX, which adheres to AT&T's Unix system V interface definition 2, and supported by PCs running the NewWave application environment. Second, an X window

Packard Ltd, Miller House, The Ring, Bracknell, Berks RG12 1XN, UK. Tel: (0734) 784774) []

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