Learning track · 18 concepts
Databases & Storage
Storage foundations for Turbopuffer-class systems: B-trees, LSM trees, WAL, compaction, partitioning, replication, object storage.
What mastery looks like
This track contains 18 connected concepts rather than an unordered reading list. Mastery means you can move from vocabulary to mechanisms, predict how the system behaves under pressure, and support a design decision with code, measurements, or a failure-recovery exercise. For Databases & Storage, use the track description as the boundary: learn enough detail to reason clearly about storage foundations for turbopuffer-class systems: b-trees, lsm trees, wal, compaction, partitioning, replication, object storage.
A useful explanation names the state involved, the operation that changes it, the resource or safety constraint, and the observable signal that tells you whether the mechanism works. Avoid stopping at product names. Compare at least two approaches, state what each optimizes, and identify what breaks first as scale, concurrency, latency, or uncertainty increases.
Suggested study sequence
Start with the core concepts at the top of the list and write a one-paragraph mechanism note for each. Continue through the core concepts by alternating explanation with an executable drill. Treat LSM Tree, Compaction, Columnar Storage, Storage Engines as integration work: they should combine earlier mechanisms rather than introduce disconnected facts.
At the end of each session, record one decision you can now make, one failure mode you can now predict, and one unanswered question. Revisit that question through the linked primary sources, then prove the answer in the Playground or a real repository. The track is complete when you can transfer the reasoning to an unfamiliar system, not when every page has been opened.
Roadmaps
Concepts in this track
core
B-Tree
The balanced, disk-friendly tree behind most relational indexes.
advanced
LSM Tree
Log-structured merge tree: write-optimized storage via sorted runs.
core
Write-Ahead Log
Append-only durability log written before the data pages.
advanced
Compaction
Merging sorted runs to reclaim space and bound read amplification.
core
Object Storage
S3-style blob storage: cheap, durable, high-latency, immutable objects.
advanced
Columnar Storage
Column-oriented layout for analytics: compression and vectorized scans.
core
Secondary Indexes
Extra indexes for non-primary-key lookups, and what they cost on writes.
advanced
Storage Engines
B-tree vs LSM, indexing, WAL.
advanced
Sharding
Range/hash/geo partitioning.
advanced
Replication
Leader-follower, multi-leader, quorum.
advanced
CAP & Consistency Models
Strong/eventual/causal, PACELC.
core
Transaction Processing
ACID, MVCC, isolation anomalies, locking, optimistic control, serializability, commit, and recovery.
core
Query Execution & Optimization
Logical and physical plans, cardinality estimation, join ordering, indexes, vectorized execution, and spilling.
core
Data Warehouses & Lakehouses
Columnar files, table formats, storage-compute separation, batch execution, metadata, governance, and lakehouse architecture.
core
Isolation Levels & MVCC
What each isolation level actually prevents, and how MVCC delivers snapshots without read locks.
core
Join Algorithms
Nested-loop, hash, and merge joins — and why cardinality estimates decide which one you get.
core
Normalization
Functional dependencies, 1NF through BCNF, and the cases where denormalising is right.
core
Buffer Pool
The database's own page cache — why it does not simply trust the OS.