Read-only replication and snapshots

Read-only replication and snapshots.

Replication
Replication is the process of copying database into one or more databases to make a system distributed.

Changes made to one database are forwarded and applied to the databases at the rest of the locations.

Advantages of Replication:

- Provides user with fast, local access to shared data,
- Protects availability of applications
- Even if one site becomes unavailable, users can continue to query or even update the remaining locations.

Read-only snapshots are used for query only. Changes made to the primary database are replicated to the snapshot by the Mobile Client.

Snapshot

- A snapshot is a full set or a subset of rows of a table or view at a point in time.
- A snapshot is created by executing a SQL query against a base table.
- Snapshots are either read-only or updateable.
- They vary in complexity.
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