apache/iceberg · error · UncheckedSQLException

Database data truncation error

Error message

Database data truncation error

What it means

Thrown by JdbcViewOperations.doCommit when a java.sql.DataTruncation occurs — a value being written (typically the metadata location string or catalog row columns) exceeded the column size in the database. Wrapped in UncheckedSQLException. The commit did not succeed.

Solutions

1. Widen the offending catalog table columns (e.g. increase VARCHAR length for metadata location) and retry
2. Shorten the warehouse path or identifiers so metadata locations fit existing column limits
3. Recreate the catalog tables using the current recommended Iceberg JDBC schema
4. Inspect the DataTruncation cause to identify which column/parameter was truncated

Example fix

// before
CREATE TABLE iceberg_views (... metadata_location VARCHAR(255) ...);
// after
ALTER TABLE iceberg_views ALTER COLUMN metadata_location TYPE VARCHAR(2048);

// Ensure metadata location fits catalog column limits
String loc = metadataFileLocation();
Preconditions.checkArgument(loc.length() <= 2048,
    "Metadata location too long for catalog columns: %s", loc.length());

try {
  view.updateSchema(apply);
} catch (UncheckedSQLException e) {
  if (e.getCause() instanceof DataTruncation) {
    // widen columns or shorten paths, then retry
  } else throw e;
}

When it happens

Trigger: Committing a view whose metadata file location or other row values exceed the length of iceberg_views columns; often after deeply nested warehouse paths or very long identifiers.

Common situations: JDBC catalog initialized with a schema that has short VARCHAR columns (or older schema versions), extremely long S3/GCS paths or namespace/table names pushing locations past column limits.

Related errors

• Cannot check and eventually update SQL schema
• Cannot initialize JDBC catalog
• Cannot initialize JDBC catalog: Connection failed
• Cannot initialize JDBC catalog: Query timed out
• Cannot initialize JDBC table maintenance lock

AI-assisted analysis of apache/iceberg@86d9c8fc54 (2026-09-12). Data as JSON: /api/errors/94bdaeb9d78da214. Report an issue: GitHub.

Appendix: source

Thrown at core/src/main/java/org/apache/iceberg/jdbc/JdbcViewOperations.java:119

          JdbcUtil.loadView(JdbcUtil.SchemaVersion.V1, connections, catalogName, viewIdentifier);
      if (base != null) {
        validateMetadataLocation(view, base);
        String oldMetadataLocation = base.metadataFileLocation();
        // Start atomic update
        LOG.debug("Committing existing view: {}", viewName());
        updateView(newMetadataLocation, oldMetadataLocation);
      } else {
        // view does not exist, create it
        LOG.debug("Committing new view: {}", viewName());
        createView(newMetadataLocation);
      }

    } catch (SQLTimeoutException e) {
      throw new UncheckedSQLException(e, "Database Connection timeout");
    } catch (SQLTransientConnectionException | SQLNonTransientConnectionException e) {
      throw new UncheckedSQLException(e, "Database Connection failed");
    } catch (DataTruncation e) {
      throw new UncheckedSQLException(e, "Database data truncation error");
    } catch (SQLWarning e) {
      throw new UncheckedSQLException(e, "Database warning");
    } catch (SQLException e) {
      if (JdbcUtil.isConstraintViolation(e)) {
        if (currentMetadataLocation() == null) {
          throw new AlreadyExistsException(e, "View already exists: %s", viewIdentifier);
        } else {
          throw new UncheckedSQLException(e, "View already exists: %s", viewIdentifier);
        }
      }

      throw new UncheckedSQLException(e, "Unknown failure");
    } catch (InterruptedException e) {
      Thread.currentThread().interrupt();
      throw new UncheckedInterruptedException(e, "Interrupted during commit");
    }
  }

View on GitHub (pinned to 86d9c8fc54)