ACID

ACID Properties IQ 

Q Define acid property in SQL Server

A ACID Property:- It is a concept for evaluation of databases and their architecture.

ACID Property: - It is a concept for evaluation of databases and their architecture.

A: - (Atomicity) – Atomicity states the principle of all or none. This means that either all the SQL Statements within the transaction will be executed or no SQL statement will be executed.

SQL Server should execute all statements inside transaction at once.  There is no partial execution of transactions.  Whatever statement given has to be executed full or none of the statements has to be executed

C: - Consistency: - Consistency states that only valid data will be written into the database. That means if any SQL transaction violets the rules or constraints define on the database to make it consistent, then all the statements within the transaction will be Rollback. Or in other words the whole transaction will be rolled back.

Whenever any change (modification) happened on parent table it automatically reflect on dependent child table

I:- Isolation :- The Isolation state that if multiple transaction try to work on the database at the same time, then these transaction will not interfere with each other. It means the second transaction will not work unless and until the previous transaction completes its work and the work is committed.

Isolation means independent. One transaction do not depend on other transaction. Users able to access multiple transactions at a time

D: - Durability: - Durability states that once the transaction is committed, then the database should not be lost in case of Software failures or hardware failures. Durability is maintained with the help of the database backups and transaction logs.

Once any transaction is updated it should be a permanent change in .mdf file