DATABASE

Today we are learning about database, here are some information about database management system.

DATABASE

A database, often abbreviated as DB, is a collection of information organized in such a way that a computer program can quickly selectdesired pieces of data.





DATABASE MANAGEMENT SYSTEM






A database management system (DBMS) is system software for creating and managing databases. The DBMS provides users and programmers with a systematic way to create, retrieve, update and manage data.

Fields, Records and Files

You can think of a traditional database as an electronic filing system, organized by fields, records, and files. A field is a single piece of information; a record is one complete set of fields; and a file is a collection of records. For example, a telephone book is analogous to a file. It contains a list of records, each of which consists of three fields: name, address, and telephone number.

An alternative concept in database design is known as Hypertext. In a Hypertext database, any object, whether it be a piece of text, a picture, or a film, can be linked to any other object. Hypertext databases are particularly useful for organizing large amounts of disparate information, but they are not designed for numerical analysis.

QUERY

-A query is a request for information from a database. There are three general methods for posing queries:

Choosing parameters from a menu: In this method, the database system presents a list of parameters from which you can choose. This is perhaps the easiest way to pose a query because the menus guide you, but it is also the least flexible.

Query by example (QBE): In this method, the systempresents a blank record and lets you specify the fields and values that define the query.

Query language: Many database systems require you to make requests for information in the form of a stylized query that must be written in a special query language. This is the most complex method because it forces you to learn a specialized language, but it is also the most powerful.

-To make a request for information from a database.

REPORT

A formatted and organized presentation of data. Most database management systems include a report writer that enables you to design and generate reports.

KEY

 In database management systems, a key is a field that you use to sort data. It can also be called a key field , sort key, index, or key word. For example, if you sort records by age, then the age field is a key. Most database management systems allow you to have more than one key so that you can sort records in different ways. One of the keys is designated the primary key, and must hold a unique value for each record. A key field that identifies records in a different table is called a foreign key.

REFERENCE:

https://searchsqlserver.techtarget.com/definition/database-management-system

https://www.webopedia.com/TERM/D/database.html

https://www.webopedia.com/TERM/D/database_management_system_DBMS.html

https://www.webopedia.com/FIG/DATABASE.gif

https://www.webopedia.com/TERM/Q/query.html

https://www.webopedia.com/TERM/K/key.html