A major change since SQL Server 2000 is the introduction of the free Express version of SQL Server 2005, designed for smaller-size database applications and to spur developer interest.
Oracle recently introduced a beta of its own free offering, the forthcoming Oracle Database 10g Express Edition.
In addition to spurring developer interest, the free version is intended to interest developers who would otherwise use less expensive open-source database alternatives, Oracle officials have said.
Both Microsofts and Oracles express editions can use only a single CPU, limit database size to 4GB and support only up to 1GB of memory, making them suited only for development of very lightweight applications.
Microsoft has offered a free version of SQL Server designed for desktop applications in MSDE (Microsoft SQL Server 2000 Desktop Engine).
SQL Server 2005 Express Edition replaces MSDE. IBM offers a comparable Personal Edition of DB2 Universal Database V8.2 for $369.
Despite the pricing discrepancy between Microsofts and IBMs basic offerings, SQL Server 2005 and DB2 are very comparable on a list-price basis and are considerably less expensive than Oracle Database 10g.
In the SQL Server 2005 family itself, there are substantial differences among the three server versions: Workgroup Edition, Standard Edition and Enterprise Edition.
The Workgroup Edition is priced at $3,899 per processor or $739 for a server with five CALs (client access licenses).
The Workgroup Edition supports a maximum of two processors and up to 3GB of memory.
Furthermore, the Workgroup Edition has a limited feature set, forgoing capabilities such as partitioning, failover clustering, fast recovery and database tuning.
Priced at $5,999 per processor or $1,849 per server with five CALs, the Standard Edition sacrifices some features found in the Enterprise Edition, including fast recovery, online indexing and partitioning.
The Standard Edition also limits processor support to four CPUs. Like the Enterprise Edition, the Standard Edition fully supports 64-bit Windows, as well as failover and database tuning.
The Enterprise Edition costs $24,999 per processor or $13,969 for a server and 25 CALs.
With the Developer Edition of SQL Server 2005, Microsoft allows customers and developers to run copies of SQL Server for development purposes without incurring a license fee. The Developer Edition includes a copy of the Enterprise Edition.
SQL Server 2005 Mobile Edition replaces SQL Server CE 2.0 and supports SQL Server 2000.
Licensing is covered through the device CAL. Using SQL Server 2005 Mobile Edition, developers can create applications for the PDA and smart-phone versions of Windows—Windows CE 5.0, Windows Mobile 2003 Software for Pocket PC and Windows Mobile 2003 Software for smart phones.
SQL Server 2005 Mobile Edition also covers applications written for Windows XP Tablet PC Edition. Standalone applications written in Mobile Edition dont require a CAL.