neilconway opened a new pull request, #20385:
URL: https://github.com/apache/datafusion/pull/20385

   ## Which issue does this PR close?
   
   - Closes #20384.
   - See #18181 for related context.
   
   ## Rationale for this change
   
   When `array_has_any` is passed a scalar for either of its argument, we can 
use a much faster algorithm: rather than doing O(N*M) comparisons for each row 
of the columnar arg, we can build a hash table on the scalar array and probe it 
instead.
   
   ## What changes are included in this PR?
   
   * Fix array_has benchmarks to actually perform UDF execution
   * Add benchmark to cover the one-scalar-arg case
   * Implement optimization as described above
   
   Note that we fallback to a linear scan when the scalar arg is smaller than a 
threshold (<= 8 elements), because benchmarks suggested probing a HashSet is 
not profitable for very small arrays.
   
   ## Are these changes tested?
   
   Yes. Tests pass and benchmarked.
   
   ## Are there any user-facing changes?
   
   No.
   


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