A database is a collection of data belonging to the same context, that is systematically stored for later use. In this sense, a library can be considered a database composed mostly of documents and texts printed on paper and indexed for reference.
Currently, due to technological development in fields such as computer and electronics, most of the databases are in digital format, and therefore offers a wide range of solutions to the problem of storing data.
The database management system (abbr. DBMS) is a suite of programs that manipulate the structure of the database, and manages access to data stored therein.
A database consists of a collection of files, the only way to access data by the DBMS, which then serves as an intermediary between the database and its users.
It receives requests for handling content and performs the necessary operations on the files. It hides the complexity of operations and provides an overview on the content.
The DBMS also allows multiple users to simultaneously manipulate the content, and can provide different views of the same set of data.
The use of databases is an alternative to traditional data storage method, by which an application places data in files handled by the application .
The use of a database instead of files facilitates the sharing of information. It automatically controls the consistency and redundancy of information, limited access to information and easier production of information from synthetic raw information.
The database will, in addition, have a unifying effect in a community that uses a database. The database administrator is responsible for organizing the contents of a database in a manner that is beneficial to the entire community of users.
A database usually requires more disk space, the wide range of functions offered by the DBMS makes more complex manipulations, and outages have a wider impact and are more difficult to catch.
Relational data model
The schema or data model is the description of the data organization. It lies within the database, and information about the characteristics of each type of data and the relationships between the various data that are in the database.
There are several types of data models (relational, entity-relationship, object, hierarchical and network).