Issues

• Spill files are validated again on read since 55.0.0

  bugperformance
  apache/datafusion#26687 · Filter by author comphead opened on Oct 23, 2026

• date_part declares a non-nullable result for non-null input, but can return NULL

  bug
  Bug

  apache/datafusion#26685 · Filter by author mbutrovich opened on Oct 23, 2026
  

• [DISCUSSION] 2026 Q4 Roadmap

  apache/datafusion#26684 · Filter by author alamb opened on Oct 23, 2026

• [EPIC] Improve I/O patterns for Parquet scans

  enhancement
  Feature

  apache/datafusion#26682 · Filter by author alamb opened on Oct 23, 2026
  1

• EXTRACT(NANOSECOND) on Duration and Interval counts whole seconds twice

  bug
  Bug

  apache/datafusion#26678 · Filter by author mbutrovich opened on Oct 23, 2026
  

• [EPIC] A Collection of Wrong Results Bugs - Q4 2026

  EPIC
  apache/datafusion#26672 · Filter by author alamb opened on Oct 23, 2026

• Comparing a Duration to an Interval with a days field returns wrong results (e.g. ts - ts <= INTERVAL '3 days')

  apache/datafusion#26671 · Filter by author mbutrovich opened on Oct 23, 2026

• Nested Parquet pruning reads every leaf through FixedSizeList, ListView and Dictionary wrappers

  performance
  apache/datafusion#26667 · Filter by author ranflarion opened on Oct 23, 2026

• [Substrait] Substrait consumer honours function declared output types

  bug
  Bug

  apache/datafusion#26665 · Filter by author dd-annarose opened on Oct 23, 2026
  1

  

• Review "db olympics" results

  enhancement
  Feature

  apache/datafusion#26661 · Filter by author alamb opened on Oct 23, 2026
  11

• LimitPushPastWindows only pushes a limit past the first window in a plan

  enhancementgood first issue
  apache/datafusion#26659 · Filter by author jayzhan211 opened on Oct 23, 2026
  1

  

• LimitPushPastWindows panics with "attempt to add with overflow" for a large ROWS ... FOLLOWING bound

  buggood first issue
  apache/datafusion#26658 · Filter by author jayzhan211 opened on Oct 23, 2026

• Incorrect ORDER BY results after sort pushdown through custom execution plans

  bug
  Bug

  apache/datafusion#26656 · Filter by author geoffreyclaude opened on Oct 23, 2026

• Minimum-value integer literal with postfix cast fails: SELECT -2147483648::INT errors in the optimizer

  apache/datafusion#26651 · Filter by author Shahzeb-DataEngineer opened on Oct 23, 2026

• sum() over DECIMAL silently wraps on overflow instead of erroring

  apache/datafusion#26648 · Filter by author Shahzeb-DataEngineer opened on Oct 23, 2026
  2

• Cannot execute pipeline breaking queries error prints the whole operator struct

  buggood first issue
  apache/datafusion#26645 · Filter by author jayzhan211 opened on Oct 23, 2026

• TopK dynamic filters don't prune inside recursive CTEs

  apache/datafusion#26642 · Filter by author jayzhan211 opened on Oct 23, 2026
  1

  

• Hash join dynamic filters don't prune inside recursive CTEs

  apache/datafusion#26641 · Filter by author jayzhan211 opened on Oct 23, 2026
  3

  

• Discuss unifying NVL and IFNULL coercion with COALESCE

  apache/datafusion#26639 · Filter by author 1fanwang opened on Oct 23, 2026

• Allow downcasting ParquetFileReaderFactory like FileSource and DataSource

  enhancement
  Feature

  apache/datafusion#26633 · Filter by author morristai opened on Oct 23, 2026

• Nested loop join filter pushdown evaluates CASE branches, OR/AND operands and coalesce arguments on every row

  bug
  Bug

  apache/datafusion#26632 · Filter by author morristai opened on Oct 23, 2026

• decorrelate_predicate_subquery removes inner LIMIT inside EXISTS even when a HAVING or WHERE above it depends on the row count

  bug
  Bug

  apache/datafusion#26629 · Filter by author wjjc1017 opened on Oct 23, 2026

• Final and Single aggregates over fully sorted input fail with ResourcesExhausted instead of emitting completed groups

  bug
  apache/datafusion#26628 · Filter by author comphead opened on Oct 23, 2026
  1

• Spill files are mostly Utf8 offsets, which zstd and lz4 barely compress

  enhancementperformance
  apache/datafusion#26627 · Filter by author comphead opened on Oct 23, 2026
  

• SanityCheckPlan error for two window functions with target_partitions = 1 (WindowAggExec loses can_repartition when its children are replaced)

  bug
  Bug

  apache/datafusion#26626 · Filter by author alpaylan opened on Oct 23, 2026