NoSQL stands for "Not Only SQL" and refers to a type of database management system that is designed to handle large amounts of unstructured or semi-structured data. It does not rely on the traditional table-based relational model and typically does not use SQL as the query language.
MongoDB, Cassandra, Redis, and Couchbase are some examples of popular NoSQL databases.
SQL databases are based on the relational model and rely on a fixed schema, while NoSQL databases are more flexible and do not have a fixed schema. SQL databases use SQL as the query language, while NoSQL databases may use different query languages. SQL databases are better suited for structured data, while NoSQL databases are better suited for unstructured or semi-structured data.
A document-based NoSQL database stores data in the form of documents, such as JSON or BSON, instead of tables. Each document contains a set of fields, similar to columns in a table, and can have a nested structure. MongoDB is an example of a document-based NoSQL database.
NoSQL databases are highly scalable and can handle large amounts of data. They are also designed to be highly available and can be distributed across multiple servers. NoSQL databases also have a more flexible schema, which allows for easier data modeling and faster development.
NoSQL databases may lack some of the advanced features of SQL databases, such as support for complex queries and transactions. They may also have less mature ecosystem and tooling.
For a social media application, a NoSQL database such as MongoDB would be suitable because it can handle large amounts of unstructured data, such as user profiles and posts. The data model would likely include collections for users, posts, comments, and likes. Indexes could be created on fields such as the user's name, the post's timestamp, and the comment's timestamp to improve the performance of queries