Learn online DBMS “Characteristics of Database Management Systems and Types of DBMS” Lesson 4

Characteristics of Database Management Systems

The main characteristics of a DBMS are as follows:
1. Self-describing nature of a database system – DBMS contains not only the database but also the description of the data that it stores. This description of data is called as meta-data. Meta-data is stored in a database catalogue or data dictionary. It contains the structure of the data and also the constraints that are imposed on the data. For example,
2. Insulation between Programs and Data – Since the definition of data is stored separately in a DBMS, any change in the structure of data would be done in the catalogue and hence programs which access this data need not be modified. This property is called as Program-Data Independence.
3. Sharing of data -A multiuser environment allows multiple users to access the database simultaneously. Thus a DBMS must include concurrency control software to allow simultaneous access of data in the database without any inconsistency problems.
Types of users of DBMS

DBMS is used by many types of users depending on their requirements and interaction with the DBMS. There are mainly four types of users:
1. End Users – Users who use the database for querying, modifying and generating reports as per their needs. They are not concerned about the working and designing of the database. They simply use the DBMS to get their task done.
2. Database Administrator (DBA) – As the name implies, the DBA administers the database and the DBMS. The DBA is responsible for authoring access, monitoring its use, provide technical support, acquiring software and hardware resources.
3. Application Programmers – writes application programs to interact with the database. These programs are written in high level languages and SQL to interact with the database.
4. System Analyst – determines the requirements of the end users and then develops specifications to meet these requirements. Basically a system analyst plays a major role in the database design, its features and analyses all the technical, economic and feasibility aspects.