Why is replication important in a distributed database?

Two Fold ReplicationThe motivation for replication is twofold:1. Increased Availability of Data: If a site that contains a replica goes down, we can find the same data at other sites. Similarly, if local copies of remote relations are available, we are less vulnerable to failure of communication links.2.

How is transactional replication used in a database?

Transactional replication is typically used in server-to-server environments. It does not simply copy the data changes, but rather consistently and accurately replicates each change. Snapshot Replication – Snapshot replication distributes data exactly as it appears at a specific moment in time does not monitor for updates to the data.

How many fragments of a database can be replicated?

Partial Replication – In this type of replication some fragments of the database may be replicated whereas others may not. The number of copies of the fragment may range from one to the total number of sites in the distributed system. The description of replication of fragments is sometimes called the replication schema.

When to use snapshot replication in a database?

Snapshot Replication – Snapshot replication distributes data exactly as it appears at a specific moment in time does not monitor for updates to the data. The entire snapshot is generated and sent to Users. Snapshot replication is generally used when data changes are infrequent.

Replication in Distributed Database. 2.  Replication is useful in improving the availability of data by coping data at multiple sites.  Either a relation or a fragment can be replicated at one or more sites.  Fully redundant databases are those in which every site contains a copy of the entire database.

Is there full replication or partial replication in DDB?

Full replication. No replication. Partial replication. 1. Replication in DDB Full, no, partial