Managing RDBMS

 

1.  What are the advantages of centralizing the RDBMS server?

·        Cost reduction in peripheral infrastructure: the net cost incurred in maintaining the server is much less than that for maintaining several computers because the RDBMS is deployed on one centralized server

·        Flexibility in organizing networks: it is easier to maintain the server and the set of clients on a network. Network traffic can be minimized because the centralized database server prioritized the request of users

·        Ease in the expansion of a network: new nodes can be easily connected to the server to add users or clients to the network

·        Improved user interface: the user interface on client computers can be personalized depending upon the requirement of the users accessing the RDBMS server

2.      What are the advantages of a parallel RDBMS architecture?

·        Increasing the number of processed transactions in a specified time

·        Reducing the request processing time

·        Speedup – process of faster query resolution due to increased availability of processors and hard disks on a computer

·        Scaleup – is the phenomenon in which a processor manages large tasks and an additional set of requests for transaction and query processing in a given time period.

3.  What are the advantages of a distributed RDBMS server?

·        Unrestricted access to data can be provided for various users

·        Database operations can be carried on despite natural disasters, such as earthquake, flood, and fire

·        The administration of data can be decentralized by distributing the database

4.  How is the data replication useful?

      Data replication enables you to copy a table or an entire database to multiple computers for several users. This ensures data availability for multiple users. It provides the following advantages for both users and administrators:

·        Data sharing

·        Reduced network traffic

·        Database backup

5.  What are the tools for monitoring database performance?

     There are four views available in the Performance Monitor tool:

·        Alert – generates a warning when any component is overused or malfunctions

·        Log – stores the activities conducted on a server

·        Chart – compares the performance of various components graphically. The graph is mapped directly to the performance of the component

·        Report – depicts the performance in the form of a report.

6.  What are the methods by which you can enhance database performance at the basic level?

      You can enhance the performance of a database by implementing measures, such as removing the duplication of data from tables. Inefficiencies can be identified and removed while designing the database.

7.  What is the contrast in the replication models?

Various replication models are used for database replication. The replication models depend on the type of organization and the requirement of the organization. An organization might decide to choose any one of the three database replication models:

 

Snapshot Database Replication Model	Transactional Database Replication Model	Merge Database Replication Model
·        The replica is an exact copy of the main database	·        It is used to replicate data as soon as a transaction takes place	·        It is used in organizations in which local users can modify their local database copies without updating the main database
·        The model is primarily used in organizations that require read-only data for research and analysis	·        It initially uses the snapshot methodology to synchronize data between the main database and local copies. Later, only the changes are updated and not the complete database	·        It is used by small organizations that do need to simultaneously or frequently update the main database. This reduces input/output operations to the main database
·        Data consistency and integrity are maintained using synchronization	·        It generates notification changes. The updating technique uses high-speed networks for disseminating information across a network	·        All the users of the database are notified of the individual changes made to the main database when the modified database is replicated across users

                                   

8.  Which is the most preferred replication model?

      A Transactional Database is the most preferred replication model, because it initially uses the snapshot methodology to synchronize data between the main database and local copies. In addition, it generates notifications on changes across a network by using the high-speed networks.

9.  What is synchronization? When is it used?

      Synchronization is the regular updating of data from these replicas to the main database. Synchronization is done at regular intervals to reduce inconsistencies.

10. How can I enhance performance by efficiently designing a database?

·        Creating the index on the primary key has reduced the request processing time

·        You can recognize tables and create large tables to enhance the speed of data retrieval. A query can be quickly answered by scanning a few large tables

11. What is the difference between data replication and a distributed database server because both these concepts involve the distribution of data?

      In the distributed database architecture, multiple database servers can process different types of requests, such as data access request and data modification request.

In the data replication process, a database is replicated across multiple users.