Minor: Improve comments on GenericByteViewArray::bytes_iter(), prefix_iter() and suffix_iter() #6306
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…_iter() and suffix_iter()
| /// Returns an iterator over the first `prefix_len` bytes of each array | ||
| /// element, including null values. | ||
| /// | ||
| /// If `prefix_len` is larger than the element's length, the iterator will |
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This feels rather surprising to me?
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Is that a statement or a question?
If you have a suggestion of how to make it less surprising perhaps @xinlifoobar would be willing to give it a try
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I guess I would have thought returning Option<&[u8]> would be perhaps more intuitive and likely perform similarly? That being said I am surprised that skipping the null mask yields performance returns, as this hasn't been my experience with regular StringArray, so my intuition about performance may be off
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Thanks for the suggestions! @tustvold.
I created a new PR #6312 to put this discussion. I did this in the early version but didn't see performance gains like this time - it did well for inline values. We might do a combination based on the bench result, e.g., null masks for prefix_iter and slice for suffix_iter.
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The results on #6312 seem to show that using null masks does indeed reduce performance
So is the conclusion that these APIs are good to go?
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I left some comments, I think this API would be better if it returned None for a prefix too long, even if it continues to not inspect null masks
tustvold
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The docs look good, we can always update should we alter the signature
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Ok, merging in these docs so they match the current code. As @tustvold says if the code needs to be updated we can also update the docs |
Which issue does this PR close?
Follow on to #6231 from @xinlifoobar
Rationale for this change
These new APIs were added in #6231 and I wanted to clarify their behavior (so we can potentailly use them in DataFusion)
What changes are included in this PR?
Update doc comments
Are there any user-facing changes?
Documentation, no functional change