# System Design
All System Design notes →Chapter 1 — Database Selection
A decision framework for SQL vs. NoSQL vs. time-series vs. graph vs. vector vs. object storage, driven by access pattern rather than familiarity.
system-design storage-systems book
Chapter 2 — Indexing
B+ trees, LSM trees, bloom filters, and secondary indexes, and why the write/read trade-off between them decides the storage engine underneath.
system-design storage-systems book
Chapter 3 — Storage Engines
How RocksDB, WiredTiger, InnoDB, and Cassandra's SSTables implement the indexing trade-offs above as production engines.
system-design storage-systems book
Chapter 4 — Data Lifecycle
Archival, tiered storage, TTLs, retention policy, and compression as the discipline that keeps storage cost from growing linearly with data volume forever.
system-design storage-systems book