Lovely Professional University 2011 B.Tech Computer Science and Engineering Database management system-assignment 2 - exam paper

5. MY SQL- MySQL is a relational database management system (RDBMS)[1] that runs as a server providing multi-user access to a number of databases. MySQL is officially pronounced /ma???skju?'?l/ ("My S-Q-L"),[2] but is often also pronounced /ma?'si?kw?l/ ("My Sequel"). It is named after developer Michael Widenius' daughter, My. The SQL phrase stands for Structured Query Language.[3]
The MySQL development project has made its source code available under the terms of the GNU General Public License, as well as under a variety ofproprietary agreements. MySQL was owned and sponsored by a single for-profit firm, the Swedish company MySQL AB, now owned by Oracle Corporation.


3. How the different components of database management system interact for transaction Processing.

ANS: The different components of database management system are:
? DBMS Engine accepts logical requests from different other DBMS subsystems, converts them into physical equivalents, and truly accesses the database and data dictionary as they exist on a storage device.
? Data Definition Subsystem helps the user create and maintain the data dictionary and describe the structure of the files in a database.
? Data Manipulation Subsystem helps the user to add, change, and delete info in a database and query it for valuable info. Software tools within the data manipulation subsystem are most often the primary interface ranging from user and the info contained in a database. It allows the user to specify its logical info requirements.
? Application Generation Subsystem contains facilities to help users develop transaction-intensive applications. It usually requires that the user perform a detailed series of tasks to process a transaction. It facilitates easy-to-use data entry screens, programming languages, and interfaces.
? Data Administration Subsystem helps users manage the overall database environment by providing facilities for backup and recovery, security management, query optimization, concurrency control, and change management.

The transaction mechanism: A database transaction mechanism ideally guarantees ACID properties in order to ensure data integrity despite concurrent user accesses (concurrency control), and faults (fault tolerance). It also maintains the integrity of the data in the database. The DBMS can maintain the integrity of the database by not allowing more than 1 user to update the identical record at the identical time. The DBMS can help prevent duplicate records via unique index constraints; for example, no 2 customers with the identical customer numbers (key fields) can be entered into the database.

Earning:   Approval pending.