Database Mirroring Option

1. Database mirroring is that it is transactional replication meets log shipping.

2. Each individual transaction log record is sent to the standby database Server, which is transactional replication-like behavior.

3. Anything written to the source database’s transaction log will be applied to the copy of the database on the other server.

4. The switch to the other database will happen automatically as the key requirement of the solution.

5. A source database, or the principal, that then sends the transaction log records to the mirror, which is the target database.

6. The instance with the principal and the instance with the mirror are partners in a database mirroring session.

7. There is a third optional instance, named the witness. The witness is required for automatic failover.

8. Database mirroring introduces the concept of transaction safety.

9. Transaction safety controls if a database mirroring session is synchronous or asynchronous.

Database mirroring will be implemented using High Performance Mode out of the three modes of operations:

High Performance mode : this mode of database mirroring is simply mirroring asynchronously.

High Safety mode : High-safety mode is when database mirroring is operating synchronously.

Replication : Replication is the technique that allows to take some of your data and make it available elsewhere. Replication works at data level. There are 3 main types of replication in SQL server.