The free version of SQL Server 2005 is the “Express” edition. Its a cut down
version of SQL Server 2005 and is ideal as an upgrade from Access, for desktop
use or small multi-user databases. Its not designed for large scale production
use, and comes with a number of limitations. The most notable limitations are:

SQL Server 2005 Express Edition Limitations
CPU 1 CPU
RAM Maximum 1 GB
Database Size Maximum 4 GB
Operating Systems Windows Server 2003 SP1 / 2000 SP4 / XP SP2 / Vista (Requires SQL Server 2005 SP2)

While Express edition will install on a machine with multiple CPUs and
more than 1GB of RAM it will not use the additional hardware. To increase
the performance of express through additional CPUs and RAM you need to
upgrade to Workstation, Standard or Enterprise edition.

Additional features of SQL Server 2005 that are limited or not available in
the Express edition:

SQL Server 2005 Express Edition
Full Text Search Only in
Express Advanced Services
Reporting Services Only in
Express Advanced Services
Management Studio

Only in
Express Advanced Services

SQL Server Integration Services (SSIS) No
Partitioned Tables No
Indexed Views No
Database Mirroring No
Profiler No
Database Tuning Advisor No
SQL Agent Job Scheduling No
Notification Services No
Web Services (HTTP Endpoints) No
Service Broker May be a Client only
Transational Replication May be a Subscriber only
Merge Replication May be a Subscriber only

More information on

Microsoft SQL Server 2005 Express Edition
can be found in the

product page
.

For a full list of

SQL Server 2005 Express Features
.


See how Express compares to other versions of SQL Server 2005
.


See how the Express and Express Advanced Services compare
.