IDS CH4

N-tier architecture?

Layers: Client, App, Database

Why not 2-tier?

Doesn’t scale well, hard to grow

N-tier benefit?

Easy to upgrade, mix hardware

Oracle?

Big relational DB company

TimesTen?

Fast RAM-based DB, writes to disk later

MongoDB?

NoSQL, document DB, uses BSON, flexible

When to use Mongo?

Web apps, flexible data, single-page editing

Mongo limits?

16MB doc size, not strong ACID

JSON vs BSON?

JSON = text, BSON = binary and smaller

Eventual consistency?

Data may mismatch temporarily, fixes later

Cassandra?

Wide-column NoSQL, Facebook built it

Wide-column DB?

Data in columns, easy to query column sets

Cassandra now?

Apache open-source, used by Netflix, Twitter

Haystack?

Facebook photo storage system

Haystack benefits?

Faster photos, less CDN needed

Vitess?

YouTube MySQL extension for fast delivery

Vitess features?

Caching, sharding, VReplication

Spanner?

Google’s global DB, combines relational + NoSQL

Spanner storage?

Split into pieces, stored globally

TrueTime?

Atomic clocks for accurate timing