Source: http://www.microsoft.com/sqlserver/en/us/product-info/compare.aspx
Scalability and performance:
| Enterprise | Standard | Web | Workgroup | Express | |
| Number of CPU's | 8 | 4 | 4 | 2 | 1 |
| Maximum memory utilized | 2TB | 64GB | 64GB | 4GB | 1GB |
| Maximum database site | 524PB | 524 PB | 524 PB | 524 PB | 10GB |
High availability:
| Enterprise | Standard | Web | Workgroup | Express | |
| Online system changes | YES | YES | YES | YES | YES |
| Log Shipping | YES | YES | YES | YES | NO |
| Database mirrowing2 | YES | YES | NO | NO | NO |
| Automatic corruption recovery from mirror | YES | YES | NO | NO | NO |
| Log stream compression | YES | YES | NO | NO | NO |
| Number of Failover clustering nodes | 16 | 2 | NO | NO | NO |
Management tools:
| Enterprise | Standard | Web | Workgroup | Express | |
| SQL Server Configuration Manager | YES | YES | YES | YES | YES |
| SQL CMD (command prompt tool) | YES | YES | YES | YES | YES |
| Database mirroring2 | YES | YES | YES | YES | YES |
| SQL Server Migration Assistant1 | YES | YES | YES | YES | NO |
| SQL Server Management Studio2 | YES | YES | YES | YES | NO |
| SQL Server Agent | YES | YES | YES | YES | NO |
| Database Engine Tuning Advisor | YES | YES | YES | YES | NO |
| DSQL Server Profiler | YES | YES | YES | YES | NO |
| Analysis Services, PowerPivot IT operation dashboard | YES | NO | NO | NO | NO |
Replication:
| Entreprise | Standard | Web | Workgroup | Express | |
| Snapshot replication | YES | YES | Subscriber only | YES | Subscriber only |
| Merge replication | YES | YES | Subscriber only | Restricted | Subscriber only |
| Transactional replication | YES | YES | Subscriber only | Restricted | Subscriber only |
| SQL Server change tracking | YES | YES | YES | YES | YES |
| Publishing data from SQL Server to non SQL Server subscribers | YES | YES | NO | NO | NO |
| Publishing data from Oracle to SQL Server | YES | NO | NO | NO | NO |
| Peer to Peer replication | YES | NO | NO | NO | NO |
