Adaptive Server Enterprise

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Adaptive Server Enterprise (ASE) (also known as "Sybase DB" or "Sybase ASE") is a relational DBMS developed by the Sybase Corporation in the 1980s.

History

Sybase’s main DBMS product was marketed as Sybase SQL Server and was co-developed for PC by Sybase, Microsoft, and Ashton-Tate. In, 1993, the co-development licensing agreement terminated, and Sybase and Microsoft continued developing their respective products. In 1996, Sybase changed the name of its product to Adaptive Server Enterprise (ASE) as a means to differentiate its SQL Server product from Microsoft SQL Server.

Storage Model

N-ary Storage Model (Row/Record)

Concurrency Control

Multi-version Concurrency Control (MVCC)

Sybase ASE uses multi-version concurrency control where all transactions are performed in the in-memory row storage or on disk MVCC, which enables the server to lock rows for writing in one session while granting access to unaltered rows in another session.

The database runs entirely in the Adaptive Server memory space (cache), so neither log nor data is ever written to disk, and I/O is not required. Its performance can be better than a disk-oriented database, at the cost of durability; in the event of memory failure, the database cannot be recovered.