pentaho/pentaho-kettle · error · KettleFileException

: Unknown storage type

Error message

 : Unknown storage type 

What it means

ValueMetaTimestamp.readData() deserializes a value from an input stream and switches on the storage type read from the wire. If the storage-type code is not one of the known STORAGE_TYPE_* constants, it throws KettleFileException 'Unknown storage type'. This indicates corrupt or incompatible binary data.

Solutions

1. Regenerate the corrupted serialized data with the same Pentaho version that reads it
2. Verify stream alignment: a desynchronization upstream can misread the storage-type byte
3. Align reader/writer Pentaho versions; do not stream rows between different Kettle releases
4. Inspect getStorageType() of the source ValueMeta before serializing

if (storageType < 0 || storageType > STORAGE_TYPE_SORTABLE) { throw new KettleFileException("Storage type out of range: " + storageType); }

try {
  value = valueMeta.readData(inputStream);
} catch (KettleFileException e) {
  LOG.error("Corrupt or incompatible row stream: " + e.getMessage());
  throw new IOException("Aborting read", e);
}

When it happens

Trigger: Reading a serialized row whose storage-type byte is negative or outside the defined range (STORAGE_TYPE_NORMAL/INDEXED/BINARY_STRING/SORTABLE); deserializing files written by a different Kettle version with new storage types.

Common situations: Kettle repository/kitchen files moved across Pentaho versions; truncated or corrupted serialized row streams; custom serialization bugs writing garbage before readData.

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

• Unable to read cache entry from data input stream
• Unable to read step info from XML node
• Unexpected error trying to decode object.
• AbortMeta.Exception.UnexpectedErrorInReadingStepInfoFromRepo…
• AddSequenceMeta.Exception.ErrorLoadingStepInfo

AI-assisted analysis of pentaho/pentaho-kettle@f3058517a1 (2026-09-13). Data as JSON: /api/errors/8f650a9980fb31ae. Report an issue: GitHub.

Appendix: source

Thrown at core/src/main/java/org/pentaho/di/core/row/value/ValueMetaTimestamp.java:647

      }

      switch ( storageType ) {
        case STORAGE_TYPE_NORMAL:
          // Handle Content -- only when not NULL
          long time = inputStream.readLong();
          int nanos = inputStream.readInt();
          Timestamp timestamp = new Timestamp( time );
          timestamp.setNanos( nanos );
          return timestamp;

        case STORAGE_TYPE_BINARY_STRING:
          return readBinaryString( inputStream );

        case STORAGE_TYPE_INDEXED:
          return readSmallInteger( inputStream ); // just an index: 4-bytes should be enough.

        default:
          throw new KettleFileException( toString() + " : Unknown storage type " + getStorageType() );
      }
    } catch ( EOFException e ) {
      throw new KettleEOFException( e );
    } catch ( SocketTimeoutException e ) {
      throw e;
    } catch ( IOException e ) {
      throw new KettleFileException( toString() + " : Unable to read value timestamp data from input stream", e );
    }
  }

  @Override
  public synchronized SimpleDateFormat getDateFormat() {
    return getDateFormat( getType() );
  }

  private synchronized SimpleDateFormat getDateFormat( int valueMetaType ) {
    if ( conversionMetadata != null ) {
      return new SimpleTimestampFormat( conversionMetadata.getDateFormat().toPattern() );

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