When do we choose a NoSQL database? Differentiate between SQL and NoSQL databases.Name any SQL and NoSQL tools also.

We choose a NoSQL database when we have the following requirements:

1. Large amounts of data: NoSQL databases are designed to handle large volumes of data that may be structured, semi-structured, or unstructured.

2. Scalability: NoSQL databases are horizontally scalable, which means they can handle more traffic simply by adding more servers to the database.

3. Speed: NoSQL databases use a variety of data models, including column, document, key-value, and graph formats. These can be faster than traditional SQL databases.

4. Flexibility: NoSQL databases allow for flexible schema. This means that unlike SQL databases, where you have to determine the schema before you can add data, with NoSQL you can add data first and then impose a schema on it.

Differences between SQL and NoSQL databases:

1. SQL databases are primarily called as Relational Databases (RDBMS); whereas NoSQL database are primarily called as non-relational or distributed database.

2. SQL databases are table based databases whereas NoSQL databases are document based, key-value pairs, graph databases or wide-column stores.

3. SQL databases have predefined schema whereas NoSQL databases have dynamic schema for unstructured data.

4. SQL databases are vertically scalable whereas the NoSQL databases are horizontally scalable.

SQL Tools: MySQL, Oracle, SQL Server, SQLite, etc.

NoSQL Tools: MongoDB, Apache Cassandra, Google Bigtable, Amazon DynamoDB, etc.