Datavail Infotech MS SQL DBA Interview Questions and Answers

Replication is the process of copying and distributing data from one database to another.

• Types of replication include snapshot replication, transactional replication, and merge replication.

• Snapshot replication copies the entire database at a specific point in time.

• Transactional replication copies only the changes made to the database since the last replication.

• Merge replication combines changes made to the database at ...read more

Failover types in cluster and always on

• In a cluster, failover can be automatic or manual

• In Always On, failover can be synchronous or asynchronous

• Automatic failover in a cluster requires a quorum of nodes to be available

• Synchronous failover in Always On ensures data consistency but can have higher latency

• Asynchronous failover in Always On has lower latency but may result in data loss

Quorum disk is a shared disk used in a Windows Server Failover Cluster to store cluster configuration data.

• Advantages: Provides a single point of reference for cluster configuration data, ensures consistency of data across all nodes, enables automatic failover of cluster resources.

• Disadvantages: Single point of failure, requires additional hardware, can be a bottleneck for cluster performance.

• Example: In a 3-node clust...read more