Hi @OptimalPyme ,
> we want to know whether the entire database is synchronised in the mirror or whether we have the option to choose individually which tables we want to synchronise.
If you mean database mirroring, it is a database level HA. You can’t choose individually table to sync. Please refer to Database Mirroring (SQL Server) and Configure database mirroring.
If you want to sync table, suggest you use transaction replication. Please refer to Transactional Replication.
By the way, if you want to sync entire database, you can also use Always ON Availability Group.
Suggest you read the blog Difference Between Always On Failover Cluster, Database Mirroring, Always On Availability Group, Replication and Log Shipping.
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