Comparison of SQL Servers

Migration from Sybase SQL Server to Microsoft SQL Server is manageable if the appropriate steps are taken. The code base for the two products was the same through their respective 4.2 releases. They still have a similar architecture, although each release of both products introduces new differences. Both databases use Transact-SQL as a common language, although the dialects have diverged since the 4.2 releases.

Sybase must ensure its SQL Server operates the same across the several platforms it supports, including the UNIX, Novell NetWare, DEC Vax, and Windows NT operating systems. Microsoft is committed to making Microsoft SQL Server the best database running on Windows NT. This frees Microsoft to take advantage of any feature available in Windows NT, while Sybase is limited to features it can implement across all of the platforms it supports.

In addition, Microsoft has devoted development resources to building Windows-based graphical tools and other ease-of-use features into Microsoft SQL Server.

The following section lists some of the features introduced in later versions of Microsoft SQL Server and Sybase SQL Server. Because Microsoft SQL Server version 4.21a and Sybase SQL Server version 4.9.2 are similar, the following lists features introduced by Microsoft after version 4.21a and by Sybase after version 4.9.2. Both companies have independently implemented many of the same features, as well as features that are unique to Sybase SQL Server or Microsoft SQL Server. Both SQL Server products have included features such as increased compliance with ANSI SQL and improved support for administering large databases. Sybase sites do not lose these important features when they migrate to Microsoft SQL Server, but they gain new Microsoft SQL Server features such as SQL Mail, scheduled tasks, and increased integration with Microsoft Office.

Sybase Versions

The only difference between the Sybase and Microsoft versions of SQL Server 4.2 was that Microsoft SQL Server included some features Sybase added in Sybase SQL Server 4.8. Sybase SQL Server 4.9.2 was not significantly different than its version 4.8. There have been two major versions of Sybase after 4.9.2: System 10 and System 11.

System 10

Sybase introduced several new features in System 10 including:

System 11

Sybase introduced additional new features in System 11 including:

Microsoft Versions

Microsoft SQL Server versions 4.2, 4.21, and 4.21a were all similar and largely compatible with Sybase SQL Server versions up to 4.9.2. In the 4.2x versions of SQL Server, Microsoft had laid the foundations of integrating the DBMS engine with Windows NT, taking full advantage of Windows NT features such as asynchronous I/O and threading, while maintaining external compatibility with the OS/2 version of SQL Server 4.2. There have been two major versions of Microsoft SQL Server since 4.21a, SQL Server 6.0 and SQL Server 6.5. In these two releases, Microsoft added new capabilities to the Windows NT-based foundation laid with the 4.2x servers.

SQL Server 6.0

These are some of the new features that were introduced with Microsoft SQL Server 6.0:

SQL Server 6.5

SQL Server 6.5 built on the success of SQL Server 6.0 by introducing several new features: