October 24, 2019
Amitraj
What is Data?
Data is nothing but facts and statistics stored or free flowing over a network, generally it's raw and unprocessed. For example: When you visit any website, they might store you IP address, that is data, in return they might add a cookie in your browser, marking you that you visited the website, that is data, your name, it's data, your age, it's data.
Data becomes information when it is processed, turning it into something meaningful. Like, based on the cookie data saved on user's browser, if a website can analyse that generally men of age 20-25 visit us more, that is information, derived from the data collected.
What is a Database?
Database is nothing but an organized form of data for easy access, storing, retrieval and managing of data. This is also known as structured form of data which can be accessed in many ways.
Larry Ellison, the co-founder of Oracle was amongst the first few, who realised the need for a software based Database Management System.
What is DBMS?
A database management system (DBMS) is a collection of interrelated data and a collection of programs to access that data.
DBMS provides us with an interface or a tool, to perform various operations like creating database, storing data in it, updating data, creating tables in the database etc.
-> DBMS also provides protection and security to the databases.
-> The primary goal of a DBMS is to provide an enviornment that is both convenient and efficient for people to use in retrieving and storing information.
Here are some examples of popular DBMS used these days:
-> MySql
-> Oracle
-> SQL Server
-> Filemaker
-> PostgreSQL
-> Clipper
-> DB/2 etc.
Characteristics of Database Management System
A database management system has following characteristics:
1. Multiple views - DBMS offers multiple views for different users. A user who is in the Sales department will have a different view of database than a person working in the Production department. This feature enables the users to have a concentrate view of the database according to their requirements.
2. Data stored into Tables - Data is never directly stored into the database. Data is stored into tables, created inside the database. DBMS also allows to have relationships between tables which makes the data more meaningful and connected. You can easily understand what type of data is stored where by looking at all the tables created in a database.
3. Real-world entity - A modern DBMS is more realistic and uses real-world entities to design its architecture. It uses the behavior and attributes too. For example, a school database may use students as an entity and their age as an attribute.
4. Reduced Redundancy - In the modern world hard drives are very cheap, but earlier when hard drives were too expensive, unnecessary repetition of data in database was a big problem. But DBMS follows Normalisation which divides the data in such a way that repetition is minimum.
5. Multiple user and Concurrent Access - DBMS allows multiple users to work on it(update, insert, delete data) at the same time and still manages to maintain the data consistency.
6. Query Language - DBMS provides users with a simple Query language, using which data can be easily fetched, inserted, deleted and updated in a database.
7. Security - The DBMS also takes care of the security of data, protecting the data from un-authorised access. In a typical DBMS, we can create user accounts with different access permissions, using which we can easily secure our data by restricting user access.
Advantages of DBMS
1. Redundancy is controlled.
2. Unauthorised access is restricted.
3. Easy retrieval of data using the Query Language.
4. Providing multiple user interfaces.
5. We now have Database Management Systems capable of storing almost infinite data.
6. Providing Backup and Recovery.
Disadvantages of DBMS
1. Difficult in accessing data.
2.Except MySQL, which is open source, licensed DBMSs are generally costly.
3.They are large in size.
4. It's Complexity.
5. Data isolation.
6. Data integrity.
7. Security problems.
Data is nothing but facts and statistics stored or free flowing over a network, generally it's raw and unprocessed. For example: When you visit any website, they might store you IP address, that is data, in return they might add a cookie in your browser, marking you that you visited the website, that is data, your name, it's data, your age, it's data.
Data becomes information when it is processed, turning it into something meaningful. Like, based on the cookie data saved on user's browser, if a website can analyse that generally men of age 20-25 visit us more, that is information, derived from the data collected.
What is a Database?
Database is nothing but an organized form of data for easy access, storing, retrieval and managing of data. This is also known as structured form of data which can be accessed in many ways.
Larry Ellison, the co-founder of Oracle was amongst the first few, who realised the need for a software based Database Management System.
What is DBMS?
A database management system (DBMS) is a collection of interrelated data and a collection of programs to access that data.
DBMS provides us with an interface or a tool, to perform various operations like creating database, storing data in it, updating data, creating tables in the database etc.
-> DBMS also provides protection and security to the databases.
-> The primary goal of a DBMS is to provide an enviornment that is both convenient and efficient for people to use in retrieving and storing information.
Here are some examples of popular DBMS used these days:
-> MySql
-> Oracle
-> SQL Server
-> Filemaker
-> PostgreSQL
-> Clipper
-> DB/2 etc.
Characteristics of Database Management System
A database management system has following characteristics:
1. Multiple views - DBMS offers multiple views for different users. A user who is in the Sales department will have a different view of database than a person working in the Production department. This feature enables the users to have a concentrate view of the database according to their requirements.
2. Data stored into Tables - Data is never directly stored into the database. Data is stored into tables, created inside the database. DBMS also allows to have relationships between tables which makes the data more meaningful and connected. You can easily understand what type of data is stored where by looking at all the tables created in a database.
3. Real-world entity - A modern DBMS is more realistic and uses real-world entities to design its architecture. It uses the behavior and attributes too. For example, a school database may use students as an entity and their age as an attribute.
4. Reduced Redundancy - In the modern world hard drives are very cheap, but earlier when hard drives were too expensive, unnecessary repetition of data in database was a big problem. But DBMS follows Normalisation which divides the data in such a way that repetition is minimum.
5. Multiple user and Concurrent Access - DBMS allows multiple users to work on it(update, insert, delete data) at the same time and still manages to maintain the data consistency.
6. Query Language - DBMS provides users with a simple Query language, using which data can be easily fetched, inserted, deleted and updated in a database.
7. Security - The DBMS also takes care of the security of data, protecting the data from un-authorised access. In a typical DBMS, we can create user accounts with different access permissions, using which we can easily secure our data by restricting user access.
Advantages of DBMS
1. Redundancy is controlled.
2. Unauthorised access is restricted.
3. Easy retrieval of data using the Query Language.
4. Providing multiple user interfaces.
5. We now have Database Management Systems capable of storing almost infinite data.
6. Providing Backup and Recovery.
Disadvantages of DBMS
1. Difficult in accessing data.
2.Except MySQL, which is open source, licensed DBMSs are generally costly.
3.They are large in size.
4. It's Complexity.
5. Data isolation.
6. Data integrity.
7. Security problems.
