FAQ on Administration in SQL Server
159. Explain the architecture of SQL Server?
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160. Different types of Backups?
o A full database backup is a full copy of the database.
o A transaction log backup copies only the transaction log.
o A differential backup copies only the database pages modified after
the last full database backup.
o A file or filegroup restore allows the recovery of just the portion
of a database that was on the failed disk.
161. What are `jobs' in SQL Server? How do we create one? What is tasks?
Using SQL Server Agent jobs, you can automate administrative tasks and
run them on a recurring basis.
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162. What is database replication? What are the different types of
replication you can set up in SQL Server? How are they used?
Replication is the process of copying/moving data between databases on
the same or different servers. SQL Server supports the following types
of replication scenarios:
Snapshot replication
Transactional replication (with immediate updating subscribers, with
queued updating subscribers)
Merge replication
163. What are the different types of replications available in
sqlserver and brief about each?
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164. What is snapshot replication how is it different from
Transactional replication?
Snapshot replication distributes data exactly as it appears at a
specific moment in time and does not monitor for updates to the data.
Snapshot replication is best used as a method for replicating data
that changes infrequently or where the most up-to-date values (low
latency) are not a requirement. When synchronization occurs, the
entire snapshot is generated and sent to Subscribers.
Snapshot replication would be preferable over transactional
replication when data changes are substantial but infrequent. For
example, if a sales organization maintains a product price list and
the prices are all updated at the same time once or twice each year,
replicating the entire snapshot of data after it has changed is
recommended. Creating new snapshots nightly is also an option if you
are publishing relatively small tables that are updated only at the
Publisher.
Snapshot replication is often used when needing to browse data such as
price lists, online catalogs, or data for decision support, where the
most current data is not essential and the data is used as read-only.
These Subscribers can be disconnected if they are not updating the data.
Snapshot replication is helpful when:
• Data is mostly static and does not change often. When it does
change, it makes more sense to publish an entirely new copy to
Subscribers.
• It is acceptable to have copies of data that are out of date for a
period of time.
• Replicating small volumes of data in which an entire refresh of the
data is reasonable.
Snapshot replication is mostly appropriate when you need to distribute
a read-only copy of data, but it also provides the option to update
data at the Subscriber. When Subscribers only read data, transactional
consistency is maintained between the Publisher and Subscribers. When
Subscribers to a snapshot publication must update data, transactional
consistency can be maintained between the Publisher and Subscriber
because the dat
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