Databases: It’s Characteristics & Components

Database is an electronic filing system. The term database is derived from the datum. Datum is the smallest unit of information. Database is a collection of large data where data is grouped according to their characteristics into tables. Also it is easily accessed, managed, and updated. Database Tables have rows and columns. The information is stored in the table in the form of rows and columns. Columns have Data type like int, char, date, byte, image etc. We can restrict the row size to maximum number of characters by setting the properties.

Computer databases typically contain aggregations of data records or files, such as sales transactions, product catalogs and inventories, and customer profiles.

Characteristics of Database Systems:

1. Performance: Response time given by database applications must be appropriate for the human-terminal dialogue. This is dependent on organization of the data.
2. Minimal Redundancy: Objective of the database System should be to eliminate data redundancy wherever possible or if redundancy cannot be avoided foe some reasons, it should be controlled.
3. Integrity:Integrity checks can also be performed at the data level itself, by checking that data values confirm to certain specified rules, e.g. value falls in a specified range.
4. Privacy and Security: The information stored in the database should be kept in such a way that it doesn’t get lost or stolen.
   Security of data means protecting data against accidental or intentional disclosure to unauthorized persons or even unauthorized modification or destruction.

Components of a Database Management system

1. Database Manager: It is an interface between low level data stored in the database and the application programs and queries submitted by the system.
2. File Manager: It manages the allocation of space on the disk storage and maintain the data structures used to represent information stored on the disk.
3. Query Processor: It translates English like statements into low level statements.
4. DML Pre-Compiler: DML stands for Data Manipulation Language. DML Pre-Copiler manages retrieval, insertion, deletion and modification of the data.
5. DDL Compiler: DDL stands for Data Definition Language. It provides the definition and description of database objects.