A second community technical preview (CTP) could help developers investigate the use of SQL Server 2008 (previously code-named Katmai) as a storage engine for hierarchical data structures such as file systems. The CTP also debuts a variety of other new features planned for SQL Server 2008, giving database developers and administrators the opportunity to test and comment on those features before the product ships in the second quarter of 2008. However, some highly billed capabilities, such as support for geospatial data types, will not be available until one of three subsequent previews that will precede the product's final release.

Reporting Services, Mirroring Improved

SQL Server is Microsoft's database management system and business intelligence (BI) platform. Its last major overhaul was SQL Server 2005, which shipped in Nov. 2005. A first preview of its next major update, SQL Server 2008, was released in June 2007 and the final version of the product is due in the second quarter of 2008.

The second SQL Server 2008 CTP, released late in July 2007, introduces a variety of new features and enhancements that could interest both database developers and database administrators. Important updates include the following:

A new architecture for Reporting Services, SQL Server's managed reporting engine, that removes the component's dependency on Internet Information Services (IIS) and consolidates its previously separate report processing, scheduling, and management services into a single component. This should simplify deployment and configuration.

A new Reporting Services charting engine, based on technology purchased from partner Dundas Data Visualization earlier in 2007, that provides more chart types than SQL Server 2005 did. However, other reporting controls purchased from Dundas, such as a calendar control, will not appear until a future SQL Server 2008 CTP.

Improved performance in database mirroring, a simplified database failover technology introduced in SQL Server 2005, could speed recovery times in the event of a database failure and reduce the network traffic generated between mirrored databases as they synchronize.

A variety of improvements to T-SQL, SQL Server's native query language, along with several new SQL Server data types, have been introduced. For example, a new data type called HierarchyID will make it easier to use SQL Server to store and manage hierarchical data structures, such as file system directories or financial reporting structures.

Availability and Resources

Microsoft released the SQL Server 2008 CTP late in July 2007, and it is generally available as a download on Microsoft's Web site (download requires registration). The company has said it will release additional CTPs about every 60 days. According to that schedule, subsequent CTPs should be available in Q3 and Q4'07. A preview in Q1'08 will probably be the last CTP before the product ships, which Microsoft has said will occur late in Q2'08. This approach reflects the SQL Server team's new take on product release cycles: instead of releasing a series of relatively feature-complete but buggy beta versions, it intends to release stable previews with each preview adding a subset of the features planned for the product's final version.

The July CTP can be downloaded at https://connect.microsoft.com/SQLServer/Downloads.

More information on SQL Server 2008 is at www.microsoft.com/sql/prodinfo/futureversion/default.mspx.

New features in SQL Server 2008 are described in "Next SQL Server Announced" on page 35 of the June 2007 Update.