fix(udf): validate query vector dimensions before computing distances#15
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anoop-narang merged 1 commit intomainfrom Mar 26, 2026
Merged
fix(udf): validate query vector dimensions before computing distances#15anoop-narang merged 1 commit intomainfrom
anoop-narang merged 1 commit intomainfrom
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Distance UDFs (l2_distance, cosine_distance, negative_dot_product) used zip() to iterate over column and query vectors, silently truncating to the shorter length on dimension mismatch. This returned wrong results instead of an error — especially dangerous on the brute-force fallback path (SELECT *) where USearch dimension validation is bypassed. For FixedSizeList: single upfront check (zero per-row cost). For List/LargeList: per-row check (one branch, negligible vs kernel).
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Summary
l2_distance,cosine_distance,negative_dot_product) usedzip()to pair column and query vectors, silently truncating to the shorter length on dimension mismatch — returning wrong results instead of an errorSELECT *with split providers), where USearch dimension validation is bypassed entirelyFixedSizeList, per-row for variable-lengthList/LargeListTest plan
udf_dimension_mismatch_select_star— key regression test: SELECT * with wrong-dim query on split providers (UDF path), now errors instead of silently truncatingudf_dimension_mismatch_fewer/udf_dimension_mismatch_more— fewer/more dims than column, caught by optimizer pathexec_split_provider_*— split-provider tests covering production topology (scan has vector, lookup doesn't)exec_split_provider_768dim_negative_dot_product— 768-dim IP-metric end-to-end with split providers