Set - 2

Question 1 :

What is a SNAPSHOT ?

Answer :

Snapshots are read-only copies of a master table located on a remote node which is periodically refreshed to reflect changes made to the master table.

Question 2 :

What is the mechanism provided by ORACLE for table replication ?

Answer :

Snapshots and SNAPSHOT LOGs

Question 3 :

What is snapshots?

Answer :

Snapshot is an object used to dynamically replicate data between distribute database at specified time intervals. In ver 7.0 they are read only.

Question 4 :

What are the various type of snapshots?

Answer :

Simple and Complex.

Question 5 :

Describe two phases of Two-phase commit ?

Answer :

Prepare phase - The global coordinator (initiating node) ask a participants to prepare (to promise to commit or rollback the transaction, even if there is a failure) Commit - Phase - If all participants respond to the coordinator that they are prepared, the coordinator asks all nodes to commit the transaction, if all participants cannot prepare, the coordinator asks all nodes to roll back the transaction.