feat(udf): POC faster min max accumulator

[devanbenz]

Which issue does this PR close?

Closes #6906

Rationale for this change

What changes are included in this PR?

Are these changes tested?

Are there any user-facing changes?

[alamb]

I think much of the filter logic is handled by accumulate_indices

datafusion/datafusion/functions-aggregate/src/count.rs

Lines 417 to 424 in f54712d

	accumulate_indices(
	group_indices,
	values.logical_nulls().as_ref(),
	opt_filter,
	|group_index| {
	self.counts[group_index] += 1;
	},
	);

You could likely avoid much of this repetition (and likely it would be faster)

It woudl also be nice to avoid the duplication between min /max by using generics. Here is how the primitive one does it (passes in a comparison function)

https://github.com/apache/datafusion/blob/main/datafusion/functions-aggregate/src/min_max.rs#L119

[alamb]

Thanks @devanbenz -- I think this is on the right track

What I suggest is:

1. We start with StringArray (rather than StringViewArray)
2. Run some benchmarks (clickbench) -- I can do this if it would help

All in all, thanks again

[devanbenz]

@alamb thanks for taking a peek. Will go ahead and implement this for StringArray as well and modify the core functionality to lean on already existing methods + make it more generic so that MAX and MIN can share code. 🫡

[alamb]

BTW here is an example of using a const generic: #12703