Introduction to Databases
Concepts in Focus
Data
Any sort of information that is stored is called data.
Examples:
- Messages & multimedia on WhatsApp
- Products and orders on Amazon
- Contact details in telephone directory, etc.
Database
An organised collection of data is called a database.
Database Management System (DBMS)
A software that is used to easily store and access data from the database in a secure way.
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Advantages
- Security: Data is stored & maintained securely.
- Ease of Use: Provides simpler ways to create & update data at the rate it is generated and updated respectively.
- Durability and Availability: Durable and provides access to all the clients at any point in time.
- Performance: Quickly accessible to all the clients(applications and stakeholders).
Types of Databases
There are different types of databases based on how we organize the data.
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Relational Database
In relational databases, the data is organised in the form of tables.
Non-Relational Database
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These four types are commonly referred as non-relational databases.
Note
- Choice of database depends on our requirements.
- Relational database is the most commonly used database.
Relational DBMS
Relational DBMS
is a DBMS designed specifically for relational databases. Relational databases organise the data in the form of tables.Examples: Oracle, PostgreSQL, MySQL, SQLite, SQL Server, IBM DB2, etc.
Non-Relational DBMS
Non-relational DBMS
is a DBMS designed specifically for non-relational databases. Non-relational databases store the data in a non-tabular form.Examples: Elasticsearch, CouchDB, DynamoDB, MongoDB, Cassandra, Redis, etc.