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Introduction to Real Time Databases

Transaction

It is said to be set of read or write operations

Query

A Transaction is said to be a query if it contains either a read or update operation


 

Commit is a point of no return, once a transaction is commited we are certain that, the changes to the database are permanent


 

ACID Properties of a General Purpose Databases

Atomicity

    An action is said to be atomic, if it either completely done or not at all.

Consistency

    A transaction transforms the database from one consistent state to another consistent state. A state is said to be a set of transactions.

Isolation

    Until and unless a transaction is committed, the actions of it are not visible to any other transactions

Durability

    After commit, the changes made to the databases are permanent


 

Conventional Databases will follow the ACID properties and it never violates

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