ACID & BASE Properties

ACID Properties (SQL Databases)

ACID ensures data reliability and consistency in relational databases by enforcing strict transactional integrity.

• Atomicity → Transactions are all-or-nothing (e.g., a bank transfer completes fully or not at all).

• Consistency → Data always remains valid according to predefined rules (e.g., referential integrity).

• Isolation → Transactions run independently to prevent conflicts (e.g., locking mechanisms).

• Durability → Once committed, data is permanently saved even after failures (e.g., disk persistence).

Best For: Banking, finance, healthcare, stock trading.

BASE Properties (NoSQL Databases)

BASE prioritizes availability and scalability over strict consistency, making it ideal for distributed systems.

• Basically Available → System remains operational despite failures (e.g., partial data availability).

• Soft State → Data may change over time due to background replication.

• Eventually Consistent → Data syncs across nodes but not instantly (e.g., DNS updates, social media posts).

Best For: Social media, e-commerce, IoT, big data analytics.

Comparison

Feature	ACID (SQL)	BASE (NoSQL)
Consistency	Strong (Immediate)	Weak (Eventual)
Availability	Lower	Higher
Scalability	Limited	Highly Scalable
Use Case	Critical transactions	High-speed, distributed systems