Database Technologies, based in Brookline, Massachusetts, has released version 2.5 of its C-Data Manager object-oriented programming and database building tool. As with most software engineering tools in this area, it enables programmers to define types of data objects as well relationships between them, but without the need to learn a new database language. Library functions call up these objects at run-time for execution in a database schema. A high level interface provides support for network and entity-relationship database models, including those of the recursive and many-to-many type. Other features include multiple keys, variable length objects, dynamic arrays, database recovery functions and multi-user support. At the low-level, data access is both sequential and random via B-tree algorithims. C-Data Manager is aimed at computer-aided design, artificial intelligence, text processing and graphics environments. Written in C, it is supported on Sun Microsystems workstations for $350, Apple Computer Macintosh, $150, MS-DOS micros, $150, and DEC VAX systems, $400.
