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Question 6 :

What is snapshot log ?

Answer :

It is a table that maintains a record of modifications to the master table in a snapshot. It is stored in the same database as master table and is only available for simple snapshots. It should be created before creating snapshots.


Question 7 :

What are the benefits of distributed options in databases?

Answer :

Database on other servers can be updated and those transactions can be grouped together with others in a logical unit.
Database uses a two phase commit.


Question 8 :

What are the options available to refresh snapshots ?

Answer :

COMPLETE - Tables are completely regenerated using the snapshots query and the master tables every time the snapshot referenced.
FAST - If simple snapshot used then a snapshot log can be used to send the changes to the snapshot tables.
FORCE - Default value. If possible it performs a FAST refresh; Otherwise it will perform a complete refresh.


Question 9 :

What is a SNAPSHOT LOG ?

Answer :

A snapshot log is a table in the master database that is associated with the master table. ORACLE uses a snapshot log to track the rows that have been updated in the master table. Snapshot logs are used in updating the snapshots based on the master table.


Question 10 :

What is Distributed database ?

Answer :

A distributed database is a network of databases managed by multiple database servers that appears to a user as single logical database. The data of all databases in the distributed database can be simultaneously accessed and modified.