apache/iceberg · error · IllegalStateException

Invalid iceberg type %s corresponding to ORC type %s

Error message

Invalid iceberg type %s corresponding to ORC type %s

What it means

GenericOrcReader.primitive() maps an Iceberg primitive type to an ORC value reader. Inside the ORC INT/long-compatible branch, a TIME or LONG Iceberg type is handled, but any other Iceberg primitive reaching that default arm is rejected with IllegalStateException because there is no valid reader mapping.

Source

Thrown at orc/src/main/java/org/apache/iceberg/data/orc/GenericOrcReader.java:128

      }

      switch (primitive.getCategory()) {
        case BOOLEAN:
          return OrcValueReaders.booleans();
        case BYTE:
          // Iceberg does not have a byte type. Use int
        case SHORT:
          // Iceberg does not have a short type. Use int
        case INT:
          return OrcValueReaders.ints();
        case LONG:
          switch (iPrimitive.typeId()) {
            case TIME:
              return GenericOrcReaders.times();
            case LONG:
              return OrcValueReaders.longs();
            default:
              throw new IllegalStateException(
                  String.format(
                      "Invalid iceberg type %s corresponding to ORC type %s",
                      iPrimitive, primitive));
          }

        case FLOAT:
          return OrcValueReaders.floats();
        case DOUBLE:
          return OrcValueReaders.doubles();
        case DATE:
          return GenericOrcReaders.dates();
        case TIMESTAMP:
          return GenericOrcReaders.timestamps();
        case TIMESTAMP_INSTANT:
          return GenericOrcReaders.timestampTzs();
        case DECIMAL:
          return GenericOrcReaders.decimals();
        case CHAR:

View on GitHub (pinned to 86d9c8fc54)

Solutions

Align the Iceberg schema with the actual ORC file schema (update the table schema).
Rewrite the data files with a matching Iceberg type.
Upgrade Iceberg to a version handling the needed type mapping.
Inspect the ORC file schema (orc-tools) to identify the offending column and correct the mapping.

Example fix

// before
Types.TimestampType ts = (Types.TimestampType) type; // treated as INT in ORC, hits default
// after
if (iPrimitive.typeId() == Types.TimestampType.class.asSubclass(...)) {
  return GenericOrcReaders.timestamp(); // use the explicitly supported reader
}

Defensive patterns

Strategy: validation

Validate before calling

// verify schema type is supported before reading
if (!SUPPORTED.get(iPrimitive.typeId())) throw new IllegalArgumentException("unsupported mapping for " + iPrimitive);

Type guard

boolean isSupportedMapping = iPrimitive instanceof Types.LongType || iPrimitive instanceof Types.TimeType;

Prevention

Keep table schema in sync with ORC file schema
Use schema evolution APIs instead of hand edits
Test read paths after schema changes
Inspect ORC file schema with orc-tools before remapping

When it happens

Trigger: Reading an ORC file whose column type maps to this switch arm while the Iceberg schema declares a primitive type not handled in that branch (type mismatch between the Iceberg schema and the ORC file written by another writer).

Common situations: Schema evolution mismatch; ORC files written by an older Iceberg version or third-party tool with types the reader doesn't expect; corrupted or hand-edited ORC type mappings.

Understand the failure class

Background: "is not a compatible type" / "cannot merge" errors: when a value's type doesn't match what the library requires — this error's family across 65 libraries.

Related errors

AI-assisted analysis of apache/iceberg@86d9c8fc54 (2026-09-12). Data as JSON: /api/errors/70690b27a4241469. Report an issue: GitHub.