apache/iceberg · error · UnsupportedOperationException

Cannot rewrite in a table

Error message

Cannot rewrite in a %s table

What it means

Iceberg throws this UnsupportedOperationException when newRewrite() is called on a read-only table. Rewriting data files commits a new snapshot, which BaseReadOnlyTable subclasses never allow. The descriptor identifies the read-only table kind.

Solutions

1. Run rewrite operations on the writable data table from catalog.loadTable(identifier).
2. Exclude metadata tables from compaction job inputs.
3. Use table.currentSnapshot()/scan APIs to plan rewrites, then commit via the data table.

Example fix

// before
table.files().newRewrite().rewriteFiles(added, deleted).commit();

// after
Table dataTable = catalog.loadTable(TableIdentifier.of("db", "tbl"));
dataTable.newRewrite().rewriteFiles(added, deleted).commit();

if (isMetadataTableName(table.name())) { throw new IllegalArgumentException("Cannot rewrite files of metadata table " + table.name()); }

boolean canRewrite = !(table instanceof BaseReadOnlyTable); // practical check: handle provenance is Catalog.loadTable

try {
  table.newRewrite().rewriteFiles(added, deleted).commit();
} catch (UnsupportedOperationException e) {
  log.error("Rewrites are not supported on read-only table {}", table.name(), e);
}

When it happens

Trigger: Calling table.newRewrite().rewriteFiles(...).commit() on a metadata table or any BaseReadOnlyTable subclass instance.

Common situations: Compaction/rewrite jobs iterating over table references that include metadata tables, or code that captured a read-only handle earlier and passes it to maintenance utilities.

Understand the failure class

Background: UnsupportedOperationException and "is not supported" errors: when a library deliberately refuses a call — this error's family across 30 libraries.

Related errors

• Cannot append to a table
• Cannot create transactions for a
• Cannot delete from a
• Cannot expire snapshots from a
• Cannot manage snapshots in a

AI-assisted analysis of apache/iceberg@86d9c8fc54 (2026-09-12). Data as JSON: /api/errors/21719638ccbf2a24. Report an issue: GitHub.

Appendix: source

Thrown at core/src/main/java/org/apache/iceberg/BaseReadOnlyTable.java:66

  public ReplaceSortOrder replaceSortOrder() {
    throw new UnsupportedOperationException(
        "Cannot update the sort order of a " + descriptor + " table");
  }

  @Override
  public UpdateLocation updateLocation() {
    throw new UnsupportedOperationException(
        "Cannot update the location of a " + descriptor + " table");
  }

  @Override
  public AppendFiles newAppend() {
    throw new UnsupportedOperationException("Cannot append to a " + descriptor + " table");
  }

  @Override
  public RewriteFiles newRewrite() {
    throw new UnsupportedOperationException("Cannot rewrite in a " + descriptor + " table");
  }

  @Override
  public RewriteManifests rewriteManifests() {
    throw new UnsupportedOperationException(
        "Cannot rewrite manifests in a " + descriptor + " table");
  }

  @Override
  public OverwriteFiles newOverwrite() {
    throw new UnsupportedOperationException("Cannot overwrite in a " + descriptor + " table");
  }

  @Override
  public RowDelta newRowDelta() {
    throw new UnsupportedOperationException(
        "Cannot remove or replace rows in a " + descriptor + " table");
  }

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