Issues

• sum(DISTINCT x) with GROUP BY uses twice the memory or more, unless the query also has count(*)

  apache/datafusion#25932 · Filter by author mkleen opened on Oct 1, 2026
  4

• Implement optimizer hook for combining partial/final aggregate in AggregateExec

  enhancement
  Feature

  apache/datafusion#25928 · Filter by author 2010YOUY01 opened on Oct 1, 2026
  

• Avoid redundant sorts for scalar subquery expressions

  apache/datafusion#25926 · Filter by author Toby1009 opened on Oct 1, 2026
  2

• Add checked time arithmetic regression coverage for scalar UDF type recovery

  apache/datafusion#25925 · Filter by author Toby1009 opened on Oct 1, 2026
  1

  

• Filtered semi/anti sort-merge join is slow on small key groups and charges each group a whole batch

  apache/datafusion#25923 · Filter by author dwsmith1983 opened on Oct 1, 2026
  1

• LEFT JOIN with struct-field ORDER BY fails ordering validation

  bug
  Bug

  apache/datafusion#25921 · Filter by author aaron-perpetual opened on Sep 30, 2026

• Add a security policy

  enhancement
  Feature

  apache/datafusion#25916 · Filter by author alamb opened on Sep 30, 2026
  

• Spark xxhash64 hashes the raw bits of a NaN instead of the canonical NaN

  bug
  apache/datafusion#25913 · Filter by author andygrove opened on Sep 30, 2026

• Expose driver-controlled stage boundaries in physical plans

  apache/datafusion#25906 · Filter by author edmondop opened on Sep 30, 2026

• Planning time grows quadratically with IN-list size on main

  bug
  Bug

  apache/datafusion#25905 · Filter by author gafiatulin opened on Sep 30, 2026

• feat: make SharedCoalescer do memory accounting for buffered batches

  enhancement
  Feature

  apache/datafusion#25904 · Filter by author gruuya opened on Sep 30, 2026
  1

• [Proposal] Readable default column names for SQL query results

  apache/datafusion#25903 · Filter by author haochunchang opened on Sep 30, 2026
  1

  

• Remove the legacy GroupedHashAggregateStream and enable_migration_aggregate

  apache/datafusion#25902 · Filter by author alamb opened on Sep 30, 2026

• Release DataFusion 57.0.0 (Dec 2026 / Jan 2027)

  apache/datafusion#25901 · Filter by author alamb opened on Sep 30, 2026

• Decorrelate a window function below a correlated equality filter by extending PARTITION BY

  apache/datafusion#25897 · Filter by author adriangb opened on Sep 30, 2026

• Report parquet decompression time as a scan metric, split by dictionary and data pages

  enhancement
  apache/datafusion#25896 · Filter by author zhuqi-lucas opened on Sep 30, 2026
  

• Add explicit phase boundaries to optimizer rules for simplicity and safety

  apache/datafusion#25894 · Filter by author 2010YOUY01 opened on Sep 30, 2026

• Recursive CTE silently casts recursive term to the static term's type, producing wrong results or a non-terminating query

  apache/datafusion#25893 · Filter by author nathanb9 opened on Sep 30, 2026

• Group by rollup/cube/etc.. fails with new type_coercion

  bug
  Bug

  apache/datafusion#25890 · Filter by author cetra3 opened on Sep 30, 2026

• Support inputless aggregate UDFs with explicit row counts

  apache/datafusion#25885 · Filter by author wudidapaopao opened on Sep 29, 2026
  1

  

• push_down_filter does not push window predicates on expression PARTITION BY keys

  enhancement
  apache/datafusion#25864 · Filter by author zhuqi-lucas opened on Sep 29, 2026
  

• Wrong results: window aggregates over RANGE ... N PRECEDING depend on batch boundaries when the ORDER BY value is NULL

  apache/datafusion#25859 · Filter by author kita-renji opened on Sep 29, 2026

• date_bin: define the semantics of negative strides

  bug
  apache/datafusion#25856 · Filter by author viirya opened on Sep 29, 2026
  3

• date_bin: month strides on s/ms/us timestamps return NULL outside the chrono DateTime range

  bug
  apache/datafusion#25855 · Filter by author viirya opened on Sep 29, 2026
  1

• Hash aggregate with a few large groups fails after spilling: spill batches are sized by rows, not bytes

  apache/datafusion#25851 · Filter by author andygrove opened on Sep 29, 2026