NoSQL, are database systems that store data in a non-relational type. They do not hold data within fixed schemas. They are preferred for querying unstructured or semi-structured data. The term SQL stands for 'Structured Query Language,' while NoSQL stands for 'Not only SQL.'

What is NoSQL?

NoSQL databases are capable of handling large volumes of dispersed data. They are not just a database system but are concerned with unstructured data. Structured data is stored in relationships like object-table within a database. Unstructured data refers to data that is not organized in this relational way, helping to derive relevant data from unrelated data, thus offering flexible data modeling and faster responses in scenarios like graphing and simulations. The purpose of NoSQL is to create highly scalable and accessible systems suitable for real-time data queries. It employs a unique querying logic instead of standard SQL query language.

How Does NoSQL Work?

NoSQL uses data models that read and manage data from non-relational databases. Unlike traditional database systems that structure data relationally in tables and rows, NoSQL can read data from environments free from schemas like tables and rows, producing meaningful results based on the unrelated data gathered, thus allowing for low latency responses to queries.

Advantages of NoSQL

Modern applications solve many issues with the advantages of NoSQL. For example, social media applications store their data in NoSQL databases. Issues like redundancy and data generation, which can cause performance issues in standard SQL databases, are resolved. The advantages of NoSQL include:

• It provides the flexibility and iterative data reading that software demands.
• It works over distributed systems, making the system predictable and scalable.
• It offers high performance compared to relational databases as it reads data from non-relational databases.
• It allows the creation of functional functions using a specific query language instead of standard SQL language.
• Data is stored without a fixed schema, and it can read schema-less data.
• Accessing APIs is easy and straightforward using common text protocols like HTTP and JSON.

Differences Between NoSQL and SQL

While the uses of NoSQL and SQL are similar, there are some differences. Let's examine this through an example. In an SQL database, a table named 'Books' might contain fields like 'Book Title,' 'ISBN,' 'Author,' 'Publisher,' 'Page Number,' and would be linked to other tables like 'Authors' and 'Publishers' for relational information. In SQL databases, tables are linked to form relationships.

In contrast, in a NoSQL database, you might find the book information stored in a document with a label structure, where both general and specific values are compiled within the same document. Attributes can be added or removed as needed without the need for linking to another document, making data readable and manageable directly.

Use Cases of NoSQL

NoSQL is preferred for systems where data volume is large and performance is critical. It is used in various applications from social media to real-time data analysis. Let’s look at some examples of NoSQL uses based on types of NoSQL:

• Key/Value: These are caching database systems where queries are pre-answered. A common example is the Redis application, which works alongside relational and non-relational databases to keep the web service’s queries up-to-date and ready to be queried at any moment.
• Document: Databases that store data in document formats suitable for create-read-update-delete operations, such as XML, JSON, BSON. Elasticsearch and MongoDB are examples of document type NoSQL databases.
• Graph: Databases that store data by establishing connections between nodes. They are suitable for applications like fraud detection, reservations, and social media analysis. Neo4j and FlockDB are some examples of graph databases.
• Wide Column: Column-oriented databases that allow for storing data in an expandable column format, where rows are less significant. Cassandra is an example of this type.