Shipping six months later than the anticipated mid 1994 release date, Emeryville, California, based Sybase Inc has finally delivered its Navigation Server multiprocessing add-on module. It is designed for unlimited scalability, provision of parallel high performance and support for more than 500Gb of data. Initially supporting its SQL Server Database Version 4.9, the Sybase 10 database is not expected to see the light of day until the end of next year. The Navigational Server boasts three different partitioning methods, meant for a variety of tables and data access types. The first, hash partitioning, is designed to spread data evenly across the partitions, so minimising data or processing imbalance, and simultaneously providing intelligent access to any row.
Additional performance
The second, range partitioning, enables related rows to be stored together in the same partition and enables additional performance where data access is tied to ranges of the partitioning key. This kind of method, however, does require more planning in order to distribute the data more evenly across partitions. The third, schema partitioning, assigns all rows of a table to a single partition, providing more efficient space use of and data access for, small tables that may not benefit from partitioning. When processing a request, a SQL query is analysed by a full function parallel optimiser, which generates parallel queries and which in turn are sent to each partition involved and executed concurrently, thereby reducing overall access time. Working in parallel, the independent processing partitions retrieve the results from each of the partitions and the Navigation Server merges these partitions sending the result to the requester. Other features of the Navigational Server include the Configurator, which aids administrators in modelling a business workload and determining the right hardware and software configuration; the Navigational Server Manager that manages the Navigational Server parallel, partitioned and high performance database as well as providing recovery facilities; parallel insert, update and delete commands enabling batch processing and lastly, transparent access, so that details of parallel processing do not need to be understood by the user. At its inception, Sybase planned to aim the Navigation Server at users seeking to perform transaction or decision support processing on large databases, but since the 4.9 Version lacks some of the features required for transaction processing in a distributed mode, the company is skewing its emphasis towards decision support and sweating for the release of System 10. Navigation Server is the result of a joint development project between AT&T Corp and Sybase, a relationship that it seems was not without its difficulties. As far back as April, Sybase’s vice-president of marketing, Stu Schuster, was blaming the delay of the Server on performance shortfalls at Navigational Server’s beta test sites but since then other reasons have surfaced. Our sister paper Unigram.X is led to believe that the problem lay with AT&T, which began engineering work on the project in San Diego. Apparently Sybase became concerned about the future of the project when AT&T began re-allocating staff to other interests. As a result, the project was renegotiated in May, with Sybase taking the reins. The delay has been seen by some industry observers as unfortunate for Sybase, which may well have lost valuable market share to rivals Oracle Corp and Informix Software Inc. Navigation Server is available now on AT&T 3600 massively parallel systems and will be available on IBM Corp, Hewlett-Packard Co and Sun Microsystems Inc systems by the third quarter of next year.
