PostgreSQL internals, advanced querying, indexes, and production tuning.
Postgres EXPLAIN plans: node types, cost interpretation, and six patterns that kill query performance on large datasets.
Compare pgvector, Pinecone, Weaviate, Qdrant, Milvus, and Chroma on performance, cost, and operational fit with real code and benchmarks.
Build RAG systems that work in production: chunking strategies, embedding selection, pgvector ops, and retrieval quality evaluation.
B-tree internals, composite index ordering, GIN for full-text search, partial indexes, and preventing index bloat in production.
How PostgreSQL's query optimizer decides, why it gets it wrong, and how to fix it with statistics targets and covering indexes.
Schema migrations on billion-row tables without downtime: expand-contract, pg_repack, gh-ost, blue-green migrations, and rollbacks.