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A database is an organized collection of an associated set of data or information in a computer system or servers. This topic contains detailed information and comprehensive knowledge of the database, its components, example, and the hierarchy through which information is managed in a database.
What Is Database?
A database is often detailed as the associate organized set of related information. The word organized implies that information is kept in such a way that the user will store, manipulate and retrieve information simply.
The word connected implies that information is often created to store information on a couple of explicit topics. For instance, if you produce information for college students, it’ll contain information regarding the scholars like roll no, name, address, and alternative data regarding the scholars.
Similarly, if the information is regarding the staff of an organization, it’ll contain the information of workers like employee ID, grade and wage, etc. all information is organized in tables.
A table is the fundamental object of the database structure. The basic purpose of a table is to store data. A table consists of rows and columns. A table is a very convenient way to store data. You can easily manipulate the data in a table.
Rows are the horizontal part of the table. It is a collection of related fields. For example, in the above table, we have three rows. Each row contains a record of a different person.
Columns are the vertical part of the table. For example, in the above table, all values under the “Name” field make a column.
Examples of Databases
Following area unit some necessary samples of databases:
Phone directory may be an easy example of information. A phone directory stores the phone numbers of various persons. You’ll be able to search Associate in Nursing telephone number from the phone directory simply as a result of all phone numbers area unit hold on in an organized approach.
A library contains thousands of books. It’s terribly tough to handle the records of these books while not information. An information system will be accustomed to storing the records of books, members of the library, issuing and recovery of the books, etc.
The user will use the information to look at the specified books simply. This information will facilitate plenty for doing analysis work.
An information system is employed to manage the accounts system of a corporation. The accounts information keeps a record of all monetary transactions. It will simply perform completely different calculations to seek out the data concerning business like annual profit, path balance, ledger, etc.
A college has several students in numerous categories. Information is also used to keep the records of the scholars, fee transactions, examination info, and alternative information of the school. You’ll be able to additionally store the attending of the scholars within the information.
Hierarchy of Information
Data in the laptop is assessed in a very hierarchy. Completely different terms area unit used to describe the information of various levels within the hierarchy. The information contains files, a file contains records, a record contains fields and a field accommodates characters.
A bit is the smallest unit of information recognized by the laptop. Eight bits create one computer memory unit. A computer memory unit is employed to represent a personality like ‘7’, ‘T’, ‘>’.
A field may be a combination of 1 or additional characters. it’s the tiniest unit of information that may be accessed by the user. A field is known unambiguously by field name. the info style of a field specifies the type of information to be held on within the field. Common information varieties area unit as follows:
- Text: accustomed store alphabetic, numbers, and special characters.
- Memo: it’s usually store extended text.
- Number: it’s used to store numeric information.
- Currency: accustomed store numeric information.
- Yes/No: it’s comfortable to store mathematician values True or False.
- Date: it’s accustomed store month, day, year and time.
- Hyperlink: it’s used to store internet address that links document or web content.
- Object: it’s familiar to store image, audio, video or a document created in alternative applications like MS Word or MS surpass.
A field size defines the utmost range of characters that may be held on in a very field.
A group of connected fields is understood as a record. For instance, a student’s record includes a group of fields concerning the scholar like student ID, Name, Address, Email, phone, etc.
A file or file may be an assortment of connected records. Files area unit hold on in disk-like magnetic disc, ROM, or DVD-ROM. A student file could contain the records of many students. Every student’s record consists of the same fields however every field contains completely different information.
The term file also can discuss with the data processing, computer program, or alternative possible application files. These area units are known as program files. These files could or might not contain information.
Information may be a cluster of connected information files. For instance, student information could have information files like students files, fee files, attending files and communicating files, etc. The information is that the data files will be accessed by the mistreatment direction system.