Which storage solution is a petabyte scale, NoSQL database?

Some of the common types of NoSQL databases are as follows:

• Graph databases: They utilize edges, properties and nodes to connect data rather than foreign keys and tables. Neo4j is a popular example.
• Column-oriented databases: Unlike relational databases which utilize rows to arrange data, they use columns
• Document databases: These databases can be used for various projects and are versatile. MongoDB and CouchDB are the popular examples.
• Multi-model databases: These databases are used for complex projects with multiple data views. Some popular examples are OrientDB and ArangoDB.

NoSQL databases offer several advantages over SQL, some of which are as follows:

• Flexibility: NoSQL databases can access and store various data structures within a database, which also includes unstructured data. This makes it easy to alter data fields. NoSQL also allows you to add attributes and fields.
• Scalability: By adding servers, NoSQL databases can scale horizontally making them suitable for large quantities of data and applications with a lot of traffic. On the other hand, SQL databases scale usually on a singular server vertically and hence can only increase storage with the help of more physical hardware.
• Performance: NoSQL databases can write or read data faster compared to SQL because they store data together. They can alter the database structure and upgrade without downtime.

NoSQL is a database design method that allows for the non-relational storing and retrieval of data. Huge amounts of data and unstructured data sets are best suited for NoSQL's processing in applications such as social networks, online gaming, and real-time web apps.

Some of the best NoSQL databases are as follows:

• MongoDB
• Cassandra
• Redis
• Neo4j
• Amazon DynamoDB
• HBase
• Elasticsearch

NoSQL databases are good for small projects if you need flexibility, scalability, or have unstructured data. But if your needs are simple, like working with organized data, SQL databases might be cheaper and simpler to use.