Showing posts with label ACID. Show all posts
Showing posts with label ACID. Show all posts

July 01, 2019

CAP Theorem

CAP theorem (also known as Eric Brewers theorem) states that we can only achieve at most two out of three guarantees for a database: Consistency, Availability and Partition Tolerance.

July 01, 2016

ACID properties in DBMS

ACID properties provide a mechanism to ensure correctness and consistency of a database in a way such that each transaction is a group of operations that acts a single unit, produces consistent results, acts in isolation from other operations and updates that it makes are durably stored.

Atomicity
The atomicity means either all the operations (insert, update, delete) inside a transaction take place or none. Or you can say, all the statements (insert, update, delete) inside a transaction are either completed or rolled back. There is no midway i.e. transactions do not occur partially. Atomicity is also known as the ‘All or nothing rule’.