what is database ? explain any two advantages of DBMS
Answers
A database is an organized collection of data, generally stored and accessed electronically from a computer system. Where databases are more complex they are often developed using formal design and modeling techniques
Answer:
A database management system (DBMS) is a software application that enables a user to define, create, and maintain a database while providing a way to maintain multiple access control and security of the data.
Before the onset of DBMS, flat file systems were used. The flat file systems stored data in single lists or tables, which could only hold limited amounts of manageable data. These tables could only be accessed with a single file at a time and generally not shared with others. Extremely large tables in flat file systems became very cumbersome to manipulate and maintain. Because of this, users often created different tables to serve different purposes irrespective of whether these tables contained similar data.
Overall, the development of the DBMS revolutionized the volume of manageable data storage. It also dramatically changed data security, how data is stored and retrieved, the ability to share data, and the number of concurrent users.
Advantages of DBMS
There are several advantages of database management systems. Chief among them are data redundancy and consistency, data sharing, integrity restrictions, and greater security.
Imagine we have a student named Jamie Wallis enrolled in a class of 300 in a school of 2,343 students. There are various pieces of information we need to store about this child and their class. A school will record personal details, like name, address, guardian, guardian contact details, emergency contact, date of birth, subjects studied, and more. In a flat file system, the student personal details table for Jamie's class alone would probably have 10 or more columns containing 300 rows. But that's not all.
We also have to record continuous assessment and exam scores for each of the 11 subjects taken by each student for each academic term completed. At this point, the table count stands at 13. Things can quickly get complicated. In a flat file system, this would be a Herculean task to establish in one table. Remember, we are just addressing one class. The teacher would, therefore, create different tables for student personal details, each subject offered, and each academic term completed. The end of the year would also find the teacher traversing multiple tables in order to consolidate a summary of each student's overall academic and performance ranking.
Data redundancy occurs when duplicate copies of the same data are stored in different places. With our student, Jamie, the teacher has to repeatedly input the name in every table it needs to appear, including the 11 subject tables. This is data redundancy. With a DBMS, data is stored in a one structured database, and data is inputted once in only one place. As a result, the teacher needs to key in Jamie's name just one time. In all other areas where this child's name is referenced, it will be taken from that particular data repository. The control of data redundancy in DBMS also saves storage space.
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Answer:
A Database Management System (DBMS) is defined as the software system that allows users to define, create, maintain and control access to the database. DBMS makes it possible for end users to create, read, update and delete data in database.
Explanation:
Advantages
ꔷReduced data redundancy.
ꔷReduced updating errors and increased consistency.
ꔷGreater data integrity and independence from applications programs.