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It would be nice to add `append_nulls` to MapBuilder, similar to `append_nulls` on `GenericListBuilder`. Appending the nulls at once, instead of using a loop has some nice performance implications: Closes apache#9431 ``` Benchmark results (1,000,000 nulls): ┌─────────────────────────┬─────────┐ │ Method │ Time │ ├─────────────────────────┼─────────┤ │ append(false) in a loop │ 2.36 ms │ ├─────────────────────────┼─────────┤ │ append_nulls(N) │ 50 µs │ └─────────────────────────┴─────────┘ ```
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scovich
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| return Err(ArrowError::InvalidArgumentError(format!( | ||
| "Cannot append to a map builder when its keys and values have unequal lengths of {} and {}", | ||
| self.key_builder.len(), | ||
| self.value_builder.len() | ||
| ))); | ||
| } |
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There are at least two copies of this now... worth pulling out into an #[inline] check function of some kind?
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Wonderful idea, just pushed the change 👍
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Out of curiosity, are there any benchmarks in the repo that show these improvements? |
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The benchmark results are in the PR description. Let me know if you want me to commit the benchmark as well. I've left it out since it is very specific. |
…fd-map-append-nulls
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Which issue does this PR close?
Closes #9431
Rationale for this change
It would be nice to add
append_nullsto MapBuilder, similar toappend_nullsonGenericListBuilder. Appending the nulls at once, instead of using a loop has some nice performance implications:What changes are included in this PR?
A new public API.
Are these changes tested?
With some fresh unit tests.
Are there any user-facing changes?
A nice and convient new public API