You plan to create a database. The database will be used by a Microsoft .NET application for a special event that will last for two days. During the event, data must be highly available. After the eve

SQL Server 2014 Enterprise includes all high availability features but is the most expensive edition, making it unnecessarily costly for a temporary two-day event database.

SQL Server 2014 Standard supports high availability features such as Basic Availability Groups and database mirroring, satisfying the high availability requirement for the two-day event. It is a one-time licensed on-premises option that can host an isolated database without affecting existing applications, and it is significantly less expensive than Enterprise edition, making it the best balance of cost and capability for this scenario.

SQL Azure (Azure SQL Database) is a cloud-based PaaS service billed on a consumption or DTU model; while it could work technically, for a two-day isolated event it may introduce ongoing subscription costs and connectivity dependencies that are less cost-effective than a locally licensed Standard edition.

SQL Server 2014 Express with Advanced Services has a 10 GB database size limit and does not support enterprise-grade high availability features such as Always On Availability Groups or failover clustering, failing the high availability requirement.