Unverified50% confidenceFactExact time
pgvector applies WHERE filtering only after the index scan; its README notes that if the filter condition matches 10% of rows, a top-10 query returns on average only 4 rows when the default hnsw.ef_search is 40.
1
Sources
50%
Confidence
Medium-term (~90 days)
Relevance
10/17/2026
First Seen
Valid until: 1/15/2027
Sources
Related Entities
Related Claims
UnverifiedSince 0.8.0, pgvector provides an iterative index scan, enabled via SET hnsw.iterative_scan = relaxed_order or strict_order, which continues expanding the scan when candidates are exhausted until enough rows for the LIMIT are collected or the hnsw.max_scan_tuples limit is reached.68% similarUnverifiedpgvector can skip the index within a transaction via SET LOCAL enable_indexscan = off to get exact answers, and Qdrant can achieve exact retrieval via "exact": true.62% similarUnverifiedThe job search API returns the same 50 job records for all queries, just in different orders; the root cause is that the deduplication logic deduplicates only by the job title string.58% similarUnverifiedAccording to benchmark data provided by the project, Pg_vectorsearch surpasses pgvector's IVFFlat and HNSW in query throughput.58% similarUnverifiedCross-encoders are only suitable for re-ranking an already narrowed candidate set (typically 20–50 items), not for scanning the full index.57% similar
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