Search Index overview

Inverted-index search engine providing full-text search, faceted filtering, relevance ranking, and aggregations over large document collections. Distinct from relational databases (which use sequential scans or B-tree indexes for exact lookups) and vector databases (which use ANN for semantic similarity). Elasticsearch and OpenSearch are the dominant enterprise choices, offering powerful query DSLs, shard-based horizontal scaling, and rich aggregation pipelines. Meilisearch and Typesense target developer-friendly, low- latency search for application search bars. Key concerns include index mapping design, analyzer configuration (language tokenization, stemming, synonyms), relevance tuning, and shard sizing.