EasyDB features a (programming language independent) Data Definition Language (DDL) for the definition of schemas. It relies on the Entity-Attribute-Relationship model. Data Manipulation Languages (DML) include a Navigational Query language (NQL) embedded in a host language (C available now, Ada in January '93), and a generic C++ class library.
On Schema Evolution (from original survey): The schema may be freely extended with new items (types, domains, attributes, entities, relationships etc.). Deletion of items is not allowed.
Data created with an older schema may co-exist with newer data. Old applications need not be recompiled when the schema is updated. Attempts by newer applications to access `older' data in an inconsistent way are detected and reported via an exception handling system.
[Tomas Lundstrom <firstname.lastname@example.org>]
Objective Systems SF AB (Ericsson) Box 1128 S-164 22 Kista, Sweden tel : +46-8-703-4591 fax : +46-8-750-8056 contact: Jaan Habma, email@example.com
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