Database Management System is a software package that has been designed to create and maintain shared collection of logically related data. A Database Management System generally facilitates the processes of Defining, Constructing and Manipulating of data. In addition to that it provides various background services including transaction management, disaster recovery and security. Data management has become a high priority issue in modern business management. Therefore to support that, database management systems providers improving their products using innovative technologies.
History
Flat File System
A Flat File is a database that stores the data in a plain text file. Each line of the file stores a single value. Each field is separated by delimiters such as commas or tabs. Although it can have multiple tables, it cannot have multiple relations as the Relational Databases have.
Relational Databases
The main advantage of Relational Database over the Flat File System is that the proper organization of data that has. A relational database also defines the relationships between those tables. In the relational databases, queries are used to fetch data with the help of the indexes. The relational database technology makes the databases efficient, lighter and faster. Some of the advantages of the relational databases are;
- Bringing tables together using relations
- Provides a structure query language (SQL) to define and manipulate data.
- Security
Object Relational Model: It is also a relational data model but with object orientation in it. It reduces the gap between the conceptual data modeling techniques and object-relational mapping.
Object-Oriented Database
An Object Oriented database is a combination of objects in a persistent storage which holds information. It is quite similar to the object oriented languages. It can be named as the fifth-generation database technology that was began to develop in mid 80’s. The real world entities are represented like an object in the Object Oriented Data Model.
Multidimensional Database
It is a database system that can be used to utilize the advantages of the databases. It is usually structured to optimize online analytical processing and data warehouse applications. The multidimensional database can receive data from a variety of relational databases and structure the information into categories and sections that can be accessed in number of different ways.
Sub Modules
Engine
There are several tasks done by the DBMS. It accepts various logical requests from various other DBMS sub systems. Then convert those requests into their physical equivalent and actually access the database and data dictionary as they exist on a storage device.
Data definition and manipulation
In Structured query languages, they have four different operations mainly to operate data. They are Select (Retrieve data from a table/tables), insert (insert data to the tables), update (update a certain field of a column) and delete (delete rows). In addition to them there are several other commands for creating, dropping databases, etc…
Administration
The database administration means the maintaining the functionalities and managing the DBMS. There are 3 main types of Administration. They are
- Operation Administration
- Development Administration
- Application Administration
There comes several tools for the database administration and they are called as native tools.
Other services
Security: The security of data is the most important thing. A DBMS allows to let several users to access the database up to several extends. In addition to that the DBMS allows setting passwords. In addition to that the DBMS allows setting passwords. Encrypting the data is another security feature provided by the advanced DBMS.
Disaster recovery: Database Management Systems allows its users to maintain backups. It makes easy to recover when there is a crash of data. In addition to that most of the DBMS provide role back to a previous state in order to undo transactions in a given period..
Indexing: Indexing makes the operations such as insert and update easy. The data is ordered randomly and the way how it was ordered is described by the logic Indexing speed up manipulation of data since it keep a summary of mata date and it make the SQL engine to access the required data without searching whole database.However indexing doesn’t seep duo the data manipulation in the case the query is conditional, like ‘select name from student where age