Neil Conway d6fb3608b0 perf: Optimize array_position for scalar needle (#20532) ...

## Which issue does this PR close?

- Closes #20530 

## Rationale for this change

The previous implementation of `array_position` used
`compare_element_to_list` for every input row. When the needle is a
scalar (quite common), we can do much better by searching over the
entire flat haystack values array with a single call to
`arrow_ord::cmp::not_distinct`. We can then iterate over the resulting
set bits to determine per-row results.

This is ~5-10x faster than the previous implementation for typical
inputs.

## What changes are included in this PR?

* Implement new fast path for `array_position` with scalar needle
* Improve docs for `array_position`
* Don't use `internal_err` to report a user-visible error

## Are these changes tested?

Yes, and benchmarked. Additional tests added in a separate PR (#20531)

## Are there any user-facing changes?

No.

2026-02-26 18:40:55 +00:00

..

aggregate_functions.md

Enforce explicit opt-in for WITHIN GROUP syntax in aggregate UDAFs (#18607)

2025-11-14 02:46:47 +00:00

data_types.md

docs: update data_types.md to reflect current Arrow type mappings (#20072)

2026-01-31 17:50:23 +00:00

ddl.md

fix: typo in sql/ddl (#19276)

2025-12-11 09:42:46 +00:00

dml.md

Fix instances of "the the" to be "the" in comments/docs (#18478)

2025-11-04 02:53:56 +00:00

explain.md

fix: Eliminate consecutive repartitions (#18521)

2025-11-11 01:33:08 +00:00

format_options.md

minor: Fix doc about write_batch_size (#19979)

2026-01-25 22:01:27 +00:00

index.rst

Fix struct casts to align fields by name (prevent positional mis-casts) (#19674)

2026-01-23 04:05:34 +00:00

information_schema.md

Add documentation for SHOW FUNCTIONS (#13868)

2024-12-21 13:57:09 -08:00

operators.md

Document SQL literal syntax and escaping (#14934)

2025-02-28 14:40:05 -05:00

prepared_statements.md

Add documentation for prepare statements. (#14639)

2025-02-13 16:13:58 -05:00

scalar_functions.md

perf: Optimize array_position for scalar needle (#20532)

2026-02-26 18:40:55 +00:00

select.md

Support JOIN pipe operator (#17969)

2025-10-10 02:08:36 +00:00

special_functions.md

fix: skip predicates on struct unnest in PushDownFilter (#16790)

2025-07-27 06:34:19 -04:00

struct_coercion.md

Fix struct casts to align fields by name (prevent positional mis-casts) (#19674)

2026-01-23 04:05:34 +00:00

subqueries.md

Fix instances of "the the" to be "the" in comments/docs (#18478)

2025-11-04 02:53:56 +00:00

window_functions.md

feat: Support FILTER clause in aggregate window functions (#17378)

2025-09-05 22:18:23 +10:00