Databases & Data Storage
NoSQL
Definition
A NoSQL (originally referring to "non-SQL" or "non-relational") database provides a mechanism for storage and retrieval of data that is modeled in means other than the tabular relations used in relational databases.
Why It Matters
NoSQL databases emerged to handle the challenges of big data and real-time web applications that relational databases were not designed for. They offer more flexibility in data models and often provide better horizontal scalability.
Contextual Example
A social media feed, which is a rapidly changing stream of unstructured data, might be stored in a NoSQL database like MongoDB or Cassandra. The flexible schema makes it easy to store posts with different structures.
Common Misunderstandings
- NoSQL does not mean "NO SQL." Many NoSQL databases support SQL-like query languages. It is better thought of as "Not Only SQL".
- There are several categories of NoSQL databases, including Document, Key-Value, Column-Family, and Graph databases.