Microsoft on Thursday made its new SQL Server 2008 database software available for public evaluation via a free download from the company's Web site.

Users looking to try out SQL Server 2008 can download a fully functional copy free of charge and run it for up to 180 days. Microsoft said trial users will receive five instructional e-mails during their test period "to help make the most of your evaluation."

Beyond that, however, Microsoft says it does not provide support for trial software.

Microsoft on Wednesday formally released SQL Server 2008 in no less than 7 editions, ranging from the high end Enterprise version to the free SQL Server Compact 3.5, and made it immediately available to subscribers of its MSDN and Technet services for IT professionals.

Microsoft is touting the high-performance aspects of the Enterprise edition.

"If you added up all of our investments in SQL Server 2008, it was data warehouse scale that got the highest level of investment," Ted Kummert, VP of Microsoft's data platform and storage division, said on a conference call Wednesday.

Among the features designed to enhance scalability are new data compression algorithms designed to let users store more information in less space. Another new feature, Resource Governor, eases management of concurrent workloads by controlling applications' CPU and memory usage.

Also debuting in SQL Server 2008 are new data types such as spatial data, and Microsoft promises better connectivity with third-party applications from ERP vendors such as Oracle and new integration points with Microsoft Office.

Microsoft said SQL Server 2008 is priced the same as the previous version of the software, SQL Server 2005, but did not provide specific details.