Issues

• Refactor HashJoinExec by splitting regular/existence join into dedicated streams

  enhancement
  Feature

  apache/datafusion#26361 · Filter by author 2010YOUY01 opened on Oct 15, 2026

• Physical CastExpr display hides nullability changes, so union coercion casts look like no-ops

  apache/datafusion#26358 · Filter by author zhuqi-lucas opened on Oct 15, 2026
  

• Memory limit test smj_with_mem_limit_1 is flaky

  apache/datafusion#26354 · Filter by author mzabaluev opened on Oct 15, 2026

• Optimize inner joins with a proven single constant row into Filter/Projection

  enhancement
  apache/datafusion#26349 · Filter by author xudong963 opened on Oct 15, 2026
  

• Add a GroupsAccumulator for array_agg(DISTINCT)

  enhancement
  apache/datafusion#26347 · Filter by author zhuqi-lucas opened on Oct 15, 2026
  

• Planning fails with "Conflicting types" when one placeholder is inferred with two types

  apache/datafusion#26343 · Filter by author adriangb opened on Oct 15, 2026

• array_repeat fails for array inputs with nonnullable elements

  bug
  Bug

  apache/datafusion#26342 · Filter by author nat-openai opened on Oct 14, 2026

• [Bug] parse_url raises on a malformed URL when ANSI mode is off, Spark returns NULL

  bugspark
  apache/datafusion#26341 · Filter by author comphead opened on Oct 14, 2026

• [Bug] unbase64 rejects input that Spark's MIME decoder accepts

  bugspark
  apache/datafusion#26340 · Filter by author comphead opened on Oct 14, 2026

• [Bug] last_day, monthname, weekday, round and unbase64 reject arguments that Spark implicitly casts

  bugspark
  apache/datafusion#26339 · Filter by author comphead opened on Oct 14, 2026

• [Bug] trunc and date_trunc handle unsupported, NULL and non-literal formats differently from Spark

  bugspark
  apache/datafusion#26338 · Filter by author comphead opened on Oct 14, 2026

• [Bug] format_string prints the unscaled value for %s of a DECIMAL and strips trailing zeros for %g

  bugspark
  apache/datafusion#26337 · Filter by author comphead opened on Oct 14, 2026

• [Bug] date_part('SECOND', ts) drops the fractional seconds, Spark returns decimal(8,6)

  bugspark
  apache/datafusion#26336 · Filter by author comphead opened on Oct 14, 2026

• [Bug] round on a DECIMAL keeps the input type, Spark reduces the scale of the result

  bugspark
  apache/datafusion#26335 · Filter by author comphead opened on Oct 14, 2026

• [Bug] pow differs from Spark for -0.0, NaN and infinite exponents

  bugspark
  apache/datafusion#26334 · Filter by author comphead opened on Oct 14, 2026

• [Bug] atan2 does not normalize -0.0 the way Spark does

  bugspark
  apache/datafusion#26333 · Filter by author comphead opened on Oct 14, 2026

• unnest drops the list item field's metadata (e.g. Arrow extension types)

  apache/datafusion#26331 · Filter by author jiayuasu opened on Oct 14, 2026

• Unparser turns NULL list literals into [] and fails on NULL struct/map literals

  bughelp wantedunparser
  apache/datafusion#26316 · Filter by author andygrove opened on Oct 14, 2026
  1

• DFSchema column lookup is a linear scan, making logical planning and type coercion quadratic in schema width

  apache/datafusion#26314 · Filter by author JoeryH opened on Oct 14, 2026
  1

• SQL planner calls LogicalPlan::using_columns() once per SELECT item, making wide nested SELECTs quadratic

  apache/datafusion#26313 · Filter by author JoeryH opened on Oct 14, 2026

• [EPIC] Reduce complexity and duplication hotspots in DataFusion

  EPIChelp wantedtech debt
  apache/datafusion#26309 · Filter by author andygrove opened on Oct 14, 2026
  3

• Merge duplicated wildcard arms in LogicalPlanBuilder project_with_validation

  enhancementgood first issuehelp wantedlogical-exprtech debt
  apache/datafusion#26308 · Filter by author andygrove opened on Oct 14, 2026
  1

• Deduplicate bucket computation in width_bucket_interval_mdn_exact

  enhancementgood first issuehelp wantedsparktech debt
  apache/datafusion#26307 · Filter by author andygrove opened on Oct 14, 2026
  3

• Use the shared aggr_test_schema in CSV scan tests instead of a local copy

  coreenhancementgood first issuehelp wantedtech debt
  apache/datafusion#26306 · Filter by author andygrove opened on Oct 14, 2026
  2

• Split PushDownFilter::rewrite into per-plan-node pushdown helpers

  enhancementhelp wantedoptimizertech debt
  apache/datafusion#26305 · Filter by author andygrove opened on Oct 14, 2026
  1