Engineering / advanced
Build and maintain retrieval indexes
Derive retrieval index behavior from metric choices, graph or partition structure, compression, filters, update paths, and measured recall.
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Module 01 advanced
Build and maintain retrieval indexes
Derive retrieval index behavior from metric choices, graph or partition structure, compression, filters, update paths, and measured recall.
- 01
Choose the geometry before choosing the index
Distinguish cosine, inner product, and squared Euclidean ranking, including normalization and zero-vector policy.
24 min - 02
Probe partitions without confusing them with answers
Derive IVF candidate selection, nprobe cost, boundary misses, and the conditions for exhaustive IVFFlat search.
24 min - 03
Compute approximate distances from compact codes
Derive product-code storage, asymmetric distance tables, and the distinction between reconstruction and ranking error.
24 min - 04
Search a graph with a bounded candidate frontier
Separate HNSW hierarchy, base-layer exploration, result count, and implementation-specific search parameters.
24 min - 05
Build useful routes instead of only short edges
Explain neighbor diversity, construction search, degree accounting, and why graph quality limits later queries.
24 min - 06
Search the eligible population without losing its routes
Define filtered ground truth and compare postfiltering, traversal restrictions, and selective exact fallback.
24 min - 07
Keep logical documents correct while index bytes change
Separate stable document identity, logical deletion, physical removal, delta overlays, and rebuild cutovers.
24 min - 08
Merge shard answers under an explicit exactness contract
Prove when local top-k suffices, then identify approximation, replica, and deduplication cases that break the proof.
24 min - 09
Measure a frontier instead of selecting one flattering number
Define exact recall with ties, held-out queries, bounded uncertainty, and comparable latency-memory operating points.
24 min - 10
Promote a compatible retrieval system as one immutable snapshot
Bind encoder geometry, codebooks, corpus versions, metadata, and serving parameters into a reviewable artifact.
24 min