Nosql database interview questions

 

NoSQL, standing for “not only SQL,” refers to databases that store and manage data differently than relational databases. NoSQL databases are designed to handle unstructured data and are known for their flexibility. They can be categorized into four main types: document, key-value, wide-column, and graph databases.

Key Features:

Unstructured Data: NoSQL is suitable for unstructured or semi-structured data.
Scalability: These databases offer horizontal scalability.
Schema-less: NoSQL databases do not require a fixed schema.

Difference between Relational database and NoSQL

Relational DatabaseNoSQL
It is used to handle data coming in low velocity.It is used to handle data coming in high velocity.
It gives only read scalability.It gives both read and write scalability.
It manages structured data.It manages all type of data.
Data arrives from one or few locations.Data arrives from many locations.
It supports complex transactions.It supports simple transactions.
It has single point of failure.No single point of failure.
It handles data in less volume.It handles data in high volume.
Transactions written in one location.Transactions written in many locations.
support ACID properties compliancedoesn’t support ACID properties
It’s difficult to make changes in database once it is definedEnables easy and frequent changes to database
Schema  is mandatory to store the dataSchema design is not required
Deployed in vertical fashion.Deployed in Horizontal fashion.



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