v0.101.0

0.101.0 (2026-08-23)

⚠ BREAKING CHANGES

• isthmus: Substrait→Calcite conversion now represents a nullable
  literal as a cast of the literal to its nullable type where it
  previously produced a bare literal with a non-nullable type, and
  converted row types become nullable accordingly. Calcite→Substrait
  conversion folds nullability-only casts over literals into nullable
  literals instead of Expression.Cast.
• isthmus: an interval_day precision outside 0 to 9 is now
  rejected instead of silently narrowed to 6. The bound is
  getMaxScale(INTERVAL_DAY_SECOND), the same one Calcite validates an
  interval qualifier against, so nothing that parses from SQL is refused.
  Converted Calcite types and generated SQL now carry the interval's
  declared precision, so INTERVAL ... DAY TO SECOND(P) replaces the
  previous fixed DAY TO SECOND(3). A Calcite interval literal whose
  declared scale is below 3 now converts to a Substrait interval_day at
  that scale, dropping the millisecond remainder towards zero, where it
  previously reported interval_day<6> and kept it.
• isthmus: Converted Substrait datetime subtraction expressions
  now use an Isthmus-owned operator without a Calcite Enumerable
  implementation. Consumers executing these plans through the Enumerable
  convention must provide an implementation or handle this operator before
  execution.
• core: DefaultExtensionCatalog.EXTENSION_TYPES is removed
  and extension:io.substrait:extension_types is no longer loaded into
  DEFAULT_COLLECTION, so code referencing the constant no longer
  compiles and plans referencing that URN — including previously
  serialized ones — no longer import. To keep reading existing plans,
  declare the point and line types in your own YAML under the original
  URN.

Features

• core: add HasExtension.withExtension for type-agnostic copies (#1135) (14dc253)
• core: handle RelCommon data for every relation type (#1069) (6b5ba4e)
• core: update to Substrait v0.101.0 (#1103) (317a3ec)

Bug Fixes

• core: derive MergeJoin's record type from both inputs (#1112) (e4c5a9e)
• core: derive precision_time from PrecisionTimeLiteral (#1136) (102bece)
• core: report the missing path when an extension resource is absent (#1115) (45181fb)
• core: write rel-level advanced extensions on exchange rels (#1101) (c08f84d)
• isthmus: preserve interval_day precision in both conversion directions (#1120) (741d4bf)
• isthmus: preserve literal nullability converting to Calcite (#1110) (3b46130)
• isthmus: use a distinct datetime subtraction operator (#1099) (d14f0fd)
• spark: accept Substrait precisions coarser than microseconds (#1128) (961f83e)

v0.100.0

0.100.0 (2026-08-16)

⚠ BREAKING CHANGES

• core: ExpressionVisitor gains
  visit(Expression.NestedMap). Direct implementors must add it;
  implementors extending AbstractExpressionVisitor inherit the
  visitFallback default and need no change. NestedList.getType() now
  reports a nullable element type when any value is nullable, rather than
  the type of the first value. Importing an Expression.Nested with no
  arm set now throws IllegalArgumentException rather than
  UnsupportedOperationException.
• validation that previously used assert now throws
  unconditionally. Callers catching AssertionError must catch
  IllegalArgumentException or IllegalStateException instead, and code
  running without -ea — i.e. most deployments — will now see these
  checks fire: VirtualTableScan and Expression.NestedList reject
  malformed input both from their builders and from ProtoRelConverter /
  ProtoExpressionConverter, and VariadicParameterConsistencyValidator
  throws IllegalArgumentException rather than AssertionError.
• isthmus: removed LiteralConverter#convert(RexLiteral, boolean)
• isthmus-cli: isthmus with no arguments reports the missing SQL on
  stderr and exits 2, where it used to print the usage on stdout and exit
  0; --help still does the latter. Passing a query together with -e /
  --expression is now rejected instead of silently ignoring the query.
• isthmus: An aggregate converted from Substrait to Calcite now
  carries the plan's declared output type instead of Calcite's inferred
  one, and may carry a binding-transport operator instead of the plain
  SqlAggFunction.

• Output types follow the plan by default
  (OutputTypeSource.PLAN_OUTPUT); pass an AggregateConversion with
  OutputTypeSource.CALCITE_INFERENCE to
  ConverterProvider.builder().aggregateConversion(...) to restore the
  previous type behavior.
• Operator identity checks on a converted AggregateCall
  (call.getAggregation() == SUM) no longer hold for wrapped calls: read
  the invocation through AggregateFunctions.boundBinding, and call
  AggregateFunctions.unwrapBound(Aggregate) before executing a
  converted plan to replace bound calls with their delegates.
• Rollup, splitting, singleton flattening and static flattening are
  disabled for wrapped calls, each of which would re-infer the
  transformed call's type or discard the call, losing the carried type
  or binding.
• An aggregate with no groupings converts back to Substrait as a single
  empty grouping rather than none.
• ParameterizedType.StringLiteral.isWildcard() now follows the type
  grammar exactly (any, any0-any9), so a declaration whose parameter
  name merely starts with "any" no longer matches every argument type
  nor shares the signature key of any. No shipped extension is
  affected.

• isthmus: the public
  io.substrait.isthmus.expression.WindowRelFunctionConverter is removed.
  No shipped ConverterProvider ever instantiated it, so no configured
  conversion path reached it, but it was public API with public
  constructors and a public convert(...), so a downstream that
  constructed it directly will no longer compile. There is no drop-in
  replacement: WindowFunctionConverter performs the same signature
  matching against SimpleExtension.WindowFunctionVariant, but yields an
  Expression.WindowFunctionInvocation rather than a
  ConsistentPartitionWindow.WindowRelFunctionInvocation.

Features

• core: support nested map expressions and import nested structs (#1062) (64a08b7)
• core: update to substrait v0.100.0 (#1082) (e65e9d4)
• isthmus-cli: explain common SQL conversion errors instead of dumping stack traces (#1060) (4a97f9b)
• isthmus: convert nested struct and map expressions to and from Calcite (#1063) (054be1b)
• isthmus: observe field reference types (#1080) (45d64e1)
• isthmus: preserve aggregate output types and semantics through Calcite (#1017) (ac000bc)

Bug Fixes

• core: make ProtoRelConverter.newTopN keep relAnchor on the way back from proto (#1088) (186ef55)
• isthmus: preserve field types in sort and aggregate references (#1090) (43da396)
• isthmus: use schema types for virtual table literals (#1065) (94900fe)
• replace assert-based validation with real exceptions (#1058) (c6e0f08)
• spark: omit dialect entries for types with no Spark sample value (#1086) (4736310)

Code Refactoring

• isthmus: remove dead WindowRelFunctionConverter and de-duplicate call converters (#1014) (5af64e9)

v0.99.0

0.99.0 (2026-08-09)

⚠ BREAKING CHANGES

• core: adds Type.Unbound and a new
  TypeVisitor.visit(Type.Unbound) method that direct TypeVisitor
  implementors must handle.

Features

• core: bump substrait to v0.99.0 (#1042) (af0d989)
• isthmus: configurable unquoted identifier casing via the ConverterProvider builder (#1037) (0af28cc), closes #983 #983 #1035 #1036
• isthmus: observe scalar function types (#1015) (243be42)
• isthmus: observe window function return types (#1059) (353fe7b)

Bug Fixes

• isthmus: route native-image metadata queries through reflective provider (#1046) (a6d4cb5)

v0.98.0

0.98.0 (2026-08-02)

⚠ BREAKING CHANGES

• isthmus: the isthmus fat jar (isthmus-<version>-all.jar — the
  all classifier / shadowRuntimeElements variant) is no longer
  published to Maven Central. Consumers that referenced it explicitly
  should depend on the regular isthmus artifact and its transitive
  dependencies instead.

🤖 Generated with AI

• the substrait git submodule is gone. Checkouts no longer need
  --recurse-submodules; the spec inputs come entirely from the substrait-packaging
  artifacts pinned in the version catalog.

Features

• isthmus: introduce a ConverterProvider builder (#1036) (8643e2f), closes #1035 #983 #1035 #1037

Build System

• isthmus: stop publishing the isthmus fat jar (#1044) (1eb3c54)
• source spec inputs from substrait-packaging artifacts, drop the submodule (#1043) (8bc8034)

v0.97.0

0.97.0 (2026-07-26)

⚠ BREAKING CHANGES

• isthmus: The SqlParser.Config-based SQL parsing entry points (public
  since v0.94.0) have been removed in favour of passing a ConverterProvider:

• SubstraitSqlStatementParser.parseStatements(String, SqlParser.Config)
• SubstraitSqlToCalcite.convertQueries(String, Prepare.CatalogReader, SqlParser.Config)
  and its 5-arg convertQueries(..., SqlValidator, RelOptCluster, SqlParser.Config) overload

To customise parser behaviour, subclass ConverterProvider, override
getSqlParserConfig(), and pass it to the ConverterProvider-based parsing methods.

• core: Fetch.getOffset()/getCount() now return
  Optional<Expression> instead of long/OptionalLong. The generated
  protobuf API also drops FetchRel.offset/count,
  HashJoinRel/MergeJoinRel.left_keys/right_keys,
  ReadRel.VirtualTable.values, and
  Expression.Literal.IntervalDayToSecond.microseconds. Reading an
  IntervalDay type with an unset precision now throws instead of
  defaulting to 6.
• core: ** type expressions in extension YAMLs are now parsed
  with conventional operator precedence, changing the parse of expressions
  that relied on the previous uniform left-to-right precedence. The
  generated protobuf API also drops Type.user_defined_type_reference.

Verification

./gradlew :core:check :isthmus:check :core:javadoc, both Spark Scala
variants (spark-3.5_2.12, spark-4.0_2.13), and
examples:substrait-spark all pass.

• core: ** the generated protobuf API drops Expression.Enum
  and the deprecated args accessors on the scalar, window, and aggregate
  function messages. Use FunctionArgument (the arguments field)
  instead.

Verification

./gradlew :core:check :isthmus:check :core:javadoc, both Spark Scala
variants (spark-3.5_2.12, spark-4.0_2.13), and
examples:substrait-spark all pass.

• Isthmus now emits id-based outer references
  (rel_anchor / rel_reference) instead of offset-based steps_out. It still
  consumes both forms, but downstream consumers that only handle steps_out
  must be updated to read rel_reference. Rel also gains an abstract
  getRelAnchor() that non-Immutables Rel implementations must implement.
• core: remove deprecated Join.JoinType.SEMI/ANTI (#1006)
• isthmus: Converting a Substrait plan that uses
  MINUS_MULTISET or INTERSECTION_PRIMARY to Calcite now throws
  UnsupportedOperationException instead of producing an incorrect
  Calcite relation. The supported set-difference operations are
  MINUS_PRIMARY (Minus all=false) and MINUS_PRIMARY_ALL (Minus all=true); the supported intersection operations are
  INTERSECTION_MULTISET (Intersect all=false) and
  INTERSECTION_MULTISET_ALL (Intersect all=true).

Features

• core: add TopNRel physical operator (#1007) (daef55b)
• core: bump substrait to v0.91.0 (#1026) (482b898), closes #870 #871
• core: bump substrait to v0.93.0 (#1027) (97db19b), closes #872 #873 #868
• core: bump substrait to v0.95.0 (#1028) (1792014), closes #1107 #863 #965
• core: bump substrait to v0.97.0 (#1032) (598350b)
• core: bump substrait to v0.98.0 (#1033) (a968058)
• id-based outer-reference resolution (Substrait 0.89.0) (#982) (2375c2e), closes #869
• isthmus: inject ConverterProvider into the SQL statement parsers (#1035) (e018342)
• isthmus: map RIGHTSHIFT to Substrait shift_right (#986) (6a44814)
• isthmus: map Substrait concat to Calcite CONCAT_FUNCTION (#1025) (a054f4f)
• isthmus: remove invalid SetOp to Calcite relation mappings (#998) (5281a1c)

Bug Fixes

• core: type outer references against the enclosing scope on proto import (#1034) (1dd1bf6)
• isthmus: elide redundant identity projections (#1009) (aa51ae9)

Code Refactoring

• core: remove deprecated Join.JoinType.SEMI/ANTI (#1006) (f625365)

v0.96.0

0.96.0 (2026-07-19)

Features

• core: support max length, scale, precision in Substrait dialect (#977) (f094981), closes #950 #808

Bug Fixes

• ci: pin semantic-release tooling and restore v0.95.0 and v0.95.1 notes (#989) (cff0d50)
• isthmus: std_dev, variance function mappings (#780) (17d3c30), closes substrait-io/substrait#1011 substrait-io/substrait#1019 #803 #807 substrait-io/substrait#1012
• isthmus: support variadic concat conversion (#1001) (91bb733)

v0.95.1

0.95.1 (2026-07-12)

Bug Fixes

• declare constants as final (#996) (a107b72)

v0.95.0

0.95.0 (2026-07-05)

⚠ BREAKING CHANGES

• core: remove deprecated Time, Timestamp, TimestampTZ types and literals (#950)
• deps: Protobuf bindings are now generated using the v4
  protobuf libraries, released in March 2024. Ensure that dependent
  projects also use the v4 protobuf-java libraries, and be aware of the
  breaking changes within the protobuf-java APIs documented at
  https://protobuf.dev/news/v26/#java-breaking-changes

Features

• core: add Substrait dialect support (#861) (ff76c77)
• core: remove deprecated Time, Timestamp, TimestampTZ types and literals (#950) (71b940f)
• isthmus: map execution context variables to/from Calcite (#976) (08c2889)

Bug Fixes

• core: add compiled output to javadocImmutable classpath (#953) (1d3ea51)
• core: validate Plan.Root output name count (#812) (4bd6b69)
• isthmus: avoid NPE from dangling correlations left by partial decorrelation (fbf2930)
• isthmus: handle LITERAL_AGG in aggregate conversion (52a32ba)
• isthmus: use reachability-metadata.json for native image build (#979) (a1e48c6)
• isthmus: use Substrait type system when building Calcite RelBuilder (#973) (b370df5), closes #954 #955

Build System

• deps: update protobuf from v3 to v4 (#962) (1516209)

v0.94.0

0.94.0 (2026-06-21)

Features

• core: support ExecutionContextVariable (#867) (a649e0d)
• support new ComparisonJoinKey field in HashJoin/MergeJoin (#845) (9c2c750)

v0.93.0

0.93.0 (2026-06-14)

⚠ BREAKING CHANGES

• core: protobuf Aggregate.Grouping.grouping_expressions field is no longer supported
• extensions: changes the visibility of the ScalarFunctionVariant.resolve() function from public to package-private

Features

• core: remove AggregateRel.Grouping.grouping_expressions (#857) (b38ca00)
• extend substrait builder api (#773) (594a168)
• extensions: support deprecation info in extensions (#846) (f7768d9)
• extensions: support impl-level description in extensions (#848) (eb453f2)
• pojo: support plan execution behavior (#791) (50acd03)