SQL Server Always On
SQL Server Always On is a high-availability and disaster recovery solution for Microsoft SQL Server databases, introduced in SQL Server 2012. It provides availability groups that allow a set of databases to fail over together, ensuring minimal downtime and data protection through synchronous or asynchronous replication across multiple servers. It enhances database availability by supporting automatic or manual failover, read-scale workloads, and backup offloading to secondary replicas.
Developers should learn SQL Server Always On when building mission-critical applications that require high availability, such as financial systems, e-commerce platforms, or healthcare databases, to ensure continuous operation during server failures or maintenance. It is essential for scenarios demanding minimal downtime, data redundancy across geographic locations, and load balancing for read-heavy workloads, making it a key skill for database administrators and backend developers in enterprise environments.