What is difference between NOSQL and SQl databases.

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Absolutely! Let's dive into the key differences between NoSQL and SQL databases within the realm of Databases & DBA technology. 1. Data Model : - SQL databases (relational databases) follow a structured format where data is stored in tables with predefined schemas. They use SQL for querying data. - NoSQL databases on the other hand use a variety of data models like document stores key-value stores wide-column stores or graph databases. The data is stored in a non-tabular format. 2. Scalability : - SQL databases are traditionally vertically scalable meaning they run on a single server and vertically scale by increasing the CPU RAM or SSD on that server. - NoSQL databases are designed to be horizontally scalable allowing for clusters of servers to be added to handle more load. 3. ACID Properties : - SQL databases guarantee ACID (Atomicity Consistency Isolation Durability) properties which ensure reliable and secure transaction processing. - NoSQL databases particularly in the case of some types like key-value stores sacrifice ACID properties for performance and scalability. 4. Schema : - In SQL databases you need to define a schema before adding data. Any changes to the schema can be complex and may require downtime. - NoSQL databases are schema-less or have a flexible schema making it easier to store semi-structured or unstructured data without requiring a predefined schema. 5. Examples : - SQL databases: MySQL PostgreSQL Oracle Database. - NoSQL databases: MongoDB Cassandra Redis. 6. Query Language : - SQL databases use Structured Query Language (SQL) for defining and manipulating the data. - NoSQL databases may use different query languages depending on their type; for example MongoDB uses a querying language similar to JSON. 7. Use Cases : - SQL databases are suitable for applications requiring complex queries and transactions like traditional business applications. - NoSQL databases are often used in big data and real-time web applications where flexibility scalability and performance are crucial. These are some of the fundamental differences between NoSQL and SQL databases within the context of Databases & DBA technology. If you need further clarification or have specific use cases in mind feel free to ask!