Overview of Database Management and Architecture

1. What is database?

A database is a logically coherent collection of data with some inherent meaning, representing some aspect of real world and which is designed, built and populated with data for a specific purpose. The key idea behind the database concept is separating the data from the application program (data independence)

2.What is DBMS?

It is a collection of programs that enables user to create and maintain a database. In other words it is general-purpose software that provides the users with the processes of defining, constructing and manipulating the database for various applications.

3. What is a Database System?

The database and DBMS software together is called as Database system.

4. What was the need for the Database approach?

The database approach was developed and adopted because of the problems associated with data being stored within application programs or within file based systems. The problem with data being stored within application programs was that it was hard to access from other places and there were limits to what could be done with the data

Why Database?

File based systems were developed as better alternatives to paper based filing systems. By having files stored on computers, the data could be accessed more efficiently. It was common practice for larger companies to have each of its departments looking after its own data. Hence file-based system were a better approach as compared to the paper-based filling system

Traditionally, data accessed through computers was stored on different storage media in the form of individual files. Files provided to be quite satisfactory so long as computerisation was limited to a few application areas and the use of computers was restricted to a few privileged users. However as actual users grew in number, the file system gave rise to many serious problems such as high level of redundancy, inconsistency in data resulting from redundancy, individual files are not suited to rapid data-changes, inability to answer adhoc queries.

Hence the discipline of Database(Database Systems) evolved in response to  these problems

Some advantages of database systems are outlined below:

Sharing of data
Consistency of data
Integrity of data
Security of data
Data independence
Allows for more analysis of the same amount of data
Improved data access and system performance
Potentially increased productivity
Increased concurrency
Improved data backups and recovery

Some potential disadvantages of database systems are the cost of implementing them, the amount of effort needed to transfer data into the database from a current system, and also the impact on the whole company if the database fails (even if only for a relatively short period).