As the role of technology becomes multi-fold in every sector, it generates huge amounts of information that can yield valuable insights about the field. This has led to a boom in data generation in the last two decades and everyone talks about a database. Let’s explore what is a database.
What is Data?
Data are units of information, often numeric, that are collected through observation. In a more technical sense, data is a set of values of qualitative or quantitative variables about one or more persons or objects, while a datum (singular of data) is a single value of a single variable.
Although the terms “data” and “information” are often used interchangeably, these terms have distinct meanings. Information is data collated to derive meaningful inferences according to its contextual requirement. Information is structured, processed, and presented with assigned meaning that improves the reliability of the data acquired.
Data are used in scientific research, businesses management (e.g., sales data, revenue, profits, stock price), finance, governance (e.g., crime rates, unemployment rates, literacy rates), and in virtually every other form of human organizational activity (e.g., censuses of the number of homeless people by non-profit organizations).
In fact, data has been described as the new oil of the digital economy.
Significance of Data
Data plays an important role in our lives. Its importance can be accessed from the following points:
- Improve People’s Lives: Data helps you to improve quality of life for people you support. Improving quality is the first and foremost among the reasons why organizations use data. In order to take proper action, an effective data system is required.
- Helps to Make Informed Decisions: Data means knowledge. Good data provides indisputable evidence, while anecdotal evidence, assumptions, or abstract observation might lead to wasted resources due to taking actions based on an incorrect conclusion.
- Helps in Making Strategy: Data increases efficiency. Effective data collection and analysis will allow you to direct scarce resources where they are most needed. Data also supports organizations to decide the priority while resource allocation.
- Helps in Achieving Desired Results: Data allows organizations to measure the effectiveness of a given strategy. When strategies are put into place to overcome a challenge, collecting data allows you to determine how well your solution is performing, and whether or not your approach needs to be changed over the long-term.
What is a Database?
A database is an organized collection of structured data to make it easily accessible, manageable, and updated. In simple words, you can say, a database is a place where the data is stored. You can visualize a database as a library. A library contains a huge collection of books of different genres, so a library is a database and books are the data.
A simple example of a database is your school’s register. All the details of the students are present in a single file. You can access the details of any student from this file. This is called a database where you can access the information of any student.
Hierarchy of Data in a Database
Data stored in computer systems form a hierarchy extending from a single bit to a database, the major record-keeping entity of a firm. Each higher rung of this hierarchy is organized from the components below it.
Data are logically organized into:
- Bits (characters)
A bit is the smallest unit of data representation (the value of a bit maybe 0 or 1). Eight bits make a byte that can represent a character or a special symbol in a character code.
A field consists of a grouping of characters. A data field represents an attribute (a characteristic or quality) of some entity (object, person, place, or event).
A combination of one or more characters is called a field. It is the smallest unit of data that can be accessed by the user. The name of each field in a record is unique. The data type of a field indicates the type of data that can be stored in the field. Each field contains one specific piece of information. A field size defines the maximum number of characters that can be stored in a field. For example, Employee Number, Employee Name, Grade, and Designation are fields.
A record represents a collection of attributes that describe a real-world entity. A record consists of fields, with each field describing an attribute of the entity.
A collection of related fields as a single unit is called a record. For example, an employee’s record includes a set of fields that contains Employee Number, Employee Name, Grade and Designation.
A file is a group of related records. Files are frequently classified by the application for which they are primarily used. A primary key in a file in the field (or fields) whose value identifies a record among others in a data file.
A collection of related records treated as a single unit is called a file. The file is also known as a data set. Files are stored in a disk like a hard disk, CD-ROM, etc. An Employee file may contain the records of all the employees in an organization. Each employee’s record consists of the same fields but each field contains different data.
The database is an integrated collection of logically related records or files. A database consolidates records previously stored in separate files into a common pool of data records that provide data for many applications. The data stored in a database is independent of the application programs using it and of the types of secondary storage devices on which it is stored.
Uses of Database System
A database system serves the following functions:
- They store data and provide facilities (tools) to search for specific records in a given set of data.
- They store special information used to manage the data. This information is called metadata and it is not shown to all the users looking at the data.
- They can solve cases where many users want to access (and possibly change) the same entities of data.
- They manage access rights (who is allowed to see the data, who can change it).
- When there are many users asking queries to the database, these must be answered faster. In this way, the last person to ask a question can get an answer in a reasonable time.
- Certain attributes are more important than others and can be used to find other data. This is called indexing. An index contains all the important data and can be used to find other data.
- They ensure that the data always has context. There are a lot of different rules that can be added to tell the database system if the data makes sense. One of the rules might say November has 30 days. This means if someone wants to enter November 31 as a date, this change will be rejected.