test(sqllogictest): stabilize parquet output_rows_skew with WITH ORDER#21898
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RatulDawar wants to merge 1 commit intoapache:mainfrom
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test(sqllogictest): stabilize parquet output_rows_skew with WITH ORDER#21898RatulDawar wants to merge 1 commit intoapache:mainfrom
RatulDawar wants to merge 1 commit intoapache:mainfrom
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CREATE EXTERNAL TABLE skew_parquet now uses WITH ORDER (x) so FileScanConfig preserves scan ordering and per-partition row counts stay deterministic with dynamic file scheduling. Refs discussion after PR apache#21351 / apache#21866. Made-with: Cursor
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Those tests are already stable, and I think the We have to fix the skipped one. The comments explains the root cause, though I'm not sure about the solution yet. |
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Yes, I think I worded myself incorrectly. I wanted to improved the coverage as mentioned in the comment by @alamb. |
2010YOUY01
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Apr 29, 2026
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2010YOUY01
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2010YOUY01
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Oh I see, this makes sense. Thank you.
It's not obvious why this fix works, let's add more comments.
| # Test parquet-only output_rows_skew metric (WITH ORDER(x) → preserve_order scan) | ||
| # -------------------------------------------- | ||
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| statement ok |
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Suggested change
| statement ok | |
| # Parquet supports dynamic work scheduling by default; per-partition data | |
| # sources might steal work from siblings, making row counts per partition | |
| # non-deterministic. Forcing `WITH ORDER` disables this behavior. | |
| statement ok |
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Summary
Adds
WITH ORDER (x)toCREATE EXTERNAL TABLE skew_parquet/skew_parquet_singleinexplain_analyze.sltsoFileScanConfigpreserves scan ordering (preserve_order), keeping per-partitionoutput_rowsstable under dynamic file scheduling (PR #21351).Related
explain_analyze.slt#21866 / Test flake inexplain_analyze.slt#21850.Testing
cargo test -p datafusion-sqllogictest --test sqllogictests -- explain_analyze(recommended before merge)Sqllogictest-only change.
Made with Cursor