pentaho/pentaho-kettle · error · KettleStepException

DenormaliserMeta.Exception.RequiredTargetFieldName

DenormaliserMeta.Exception.RequiredTargetFieldName

Error message

DenormaliserMeta.Exception.RequiredTargetFieldName

What it means

In DenormaliserMeta.getFields, every configured target field must have a non-empty field name, because the step removes those source columns from the row before re-adding the denormalized (pivoted) targets. If the i-th target field's name is null or empty, a KettleStepException identifies the offending entry by ordinal (i+1).

Solutions

1. Open the Denormaliser dialog and fill in the missing target field name (the message tells you which entry number is blank).
2. Delete blank/unused rows from the target fields table.
3. If injecting metadata, ensure every target-field row includes a non-empty field name.
4. In code, always call setFieldName(...) on each DenormaliserTargetField before use.

Example fix

// before
targets[2].setFieldName(null);
// after
targets[2].setFieldName("amount");

for (int i = 0; i < targets.length; i++) {
  if (targets[i].getFieldName() == null || targets[i].getFieldName().isEmpty()) {
    throw new IllegalArgumentException("Target field " + (i + 1) + " has no name");
  }
}

try { transMeta.getFields(...); } catch (KettleStepException e) { log.error("Denormaliser target field #? blank: {}", e.getMessage()); }

When it happens

Trigger: getFields iterates denormaliserTargetField and encounters an entry whose getFieldName() is null or "" — thrown with the 1-based index of the bad entry.

Common situations: A partially filled target-field row in the Denormaliser dialog (name left blank but other settings entered); metadata injection mapping that skips a field name; programmatic construction of DenormaliserMeta with a default-constructed target field.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• DenormaliserMeta.Exception.RequiredKeyField
• GPBulkLoaderMeta.Exception.TableNotSpecified
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AI-assisted analysis of pentaho/pentaho-kettle@f3058517a1 (2026-09-13). Data as JSON: /api/errors/ec71f629b14cc9d3. Report an issue: GitHub.

Appendix: source

Thrown at engine/src/main/java/org/pentaho/di/trans/steps/denormaliser/DenormaliserMeta.java:182

        throw new KettleStepException( BaseMessages.getString(
          PKG, "DenormaliserMeta.Exception.UnableToLocateKeyField", keyField ) );
      }
      row.removeValueMeta( idx );
    } else {
      throw new KettleStepException( BaseMessages.getString( PKG, "DenormaliserMeta.Exception.RequiredKeyField" ) );
    }

    // Remove all field value(s) (there will be different entries for each output row)
    //
    for ( int i = 0; i < denormaliserTargetField.length; i++ ) {
      String fieldname = denormaliserTargetField[i].getFieldName();
      if ( fieldname != null && fieldname.length() > 0 ) {
        int idx = row.indexOfValue( fieldname );
        if ( idx >= 0 ) {
          row.removeValueMeta( idx );
        }
      } else {
        throw new KettleStepException( BaseMessages.getString(
          PKG, "DenormaliserMeta.Exception.RequiredTargetFieldName", ( i + 1 ) + "" ) );
      }
    }

    // Re-add the target fields
    for ( int i = 0; i < denormaliserTargetField.length; i++ ) {
      DenormaliserTargetField field = denormaliserTargetField[i];
      try {
        ValueMetaInterface target =
          ValueMetaFactory.createValueMeta( field.getTargetName(), field.getTargetType() );
        target.setOrigin( name );
        target.setConversionMask( field.getTargetFormat() );
        target.setLength( field.getTargetLength(), field.getTargetPrecision() );
        target.setCurrencySymbol( field.getTargetCurrencySymbol() );
        target.setDecimalSymbol( field.getTargetDecimalSymbol() );
        target.setGroupingSymbol( field.getTargetGroupingSymbol() );
        row.addValueMeta( target );
      } catch ( Exception e ) {

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