Database
Source: Scaling up to your first 10 million users
Relational database management system (RDBMS)
A relational database like SQL is a collection of data items organized in tables.
ACID is a set of properties of relational database transactions.
- Atomicity – Each transaction is all or nothing
- Consistency – Any tranaction will bring the database from one valid state to another
- Isolation – Excuting transactions concurrently has the same results as if the transactions were executed serially
- Durability – Once a transaction has been committed, it will remain so
There are many techniques to scale a relational database: master-slave replication, master-master replication, federation, sharding, denormalization, and SQL tuning.
