BASE Properties For Distributed Database Transactions - Partition Tolerance ve Availability Önemlidir

Giriş
Bu kavram CAP teoremi ile ilgili. CAP teoremi bir Distributed Data Store kullanıyorsak, Consistency, Availability, Partition Tolerance üçlüsünün aynı anda sağlanamayacağını söylüyor. 

BASE kısaltması Basically Available, Soft State, Eventual Consistency anlamına gelir. 

Dağıtık BASE sistemler CAP teoremindeki Consistency 'den feragat ederek diğer ikisini sağlıyor. Açıklaması şöyle

However, in distributed systems, we cannot avoid partition. Hence, a distributed system must choose between consistency (C) and availability (A), which are both important.

The ACID-type database chooses consistency (C), which means if data is not consistent, no response is provided.

The BASE database chooses availability and compromises consistency. This means it responds with local data that might not be consistent.

Designing Data Intensive Applications kitabındaki açıklama şöyle

Systems that do not meet the ACID criteria are sometimes called BASE, which stands for Basically Available, Soft state, and Eventual consistency. This is even more vague than the definition of ACID. It seems that the only sensible definition of BASE is “not ACID”; i.e., it can mean almost anything you want.

Yani BASE özelliğine Being Available with Eventual Consistency de denilebilir.

ACID ve BASE Farkı

Açıklaması şöyle

ACID focuses on Consistency and availability.

BASE focuses on Partition tolerance and availability and throws consistency out the window.

Basically Available
Örnek ver

Soft State
Açıklaması şöyle

Soft state means that the data may change later due to the eventual consistency

Eventual Consistency

Eventual Consistency yazısına taşıdım.