apache/seatunnel · error · ElasticsearchConnectorException

COMMON_UNSUPPORTED_OPERATION

COMMON_UNSUPPORTED_OPERATION

Error message

Unsupported type: 

What it means

KeyExtractor formats primary-key fields into a string key for Elasticsearch document _id generation. Nested or collection types (ROW, ARRAY, MAP) cannot be rendered as a flat key string, so the library throws ElasticsearchConnectorException with UNSUPPORTED_OPERATION when a primary key column has one of those SQL types.

Source

Thrown at seatunnel-connectors-v2/connector-elasticsearch/src/main/java/org/apache/seatunnel/connectors/seatunnel/elasticsearch/serialize/KeyExtractor.java:77

        List<FieldFormatter> fieldFormatters = new ArrayList<>(primaryKeys.length);
        for (String fieldName : primaryKeys) {
            int fieldIndex = rowType.indexOf(fieldName);
            SeaTunnelDataType<?> fieldType = rowType.getFieldType(fieldIndex);
            FieldFormatter fieldFormatter = createFieldFormatter(fieldIndex, fieldType);
            fieldFormatters.add(fieldFormatter);
        }
        return new KeyExtractor(fieldFormatters.toArray(new FieldFormatter[0]), keyDelimiter);
    }

    private static FieldFormatter createFieldFormatter(
            int fieldIndex, SeaTunnelDataType fieldType) {
        return row -> {
            switch (fieldType.getSqlType()) {
                case ROW:
                case ARRAY:
                case MAP:
                    throw new ElasticsearchConnectorException(
                            CommonErrorCodeDeprecated.UNSUPPORTED_OPERATION,
                            "Unsupported type: " + fieldType);
                case DATE:
                    LocalDate localDate = (LocalDate) row.getField(fieldIndex);
                    return localDate.toString();
                case TIME:
                    LocalTime localTime = (LocalTime) row.getField(fieldIndex);
                    return localTime.toString();
                case TIMESTAMP:
                    LocalDateTime localDateTime = (LocalDateTime) row.getField(fieldIndex);
                    return localDateTime.toString();
                default:
                    return row.getField(fieldIndex).toString();
            }
        };
    }

    private interface FieldFormatter extends Serializable {

View on GitHub (pinned to cf67b549a7)

Solutions

1. Change the primary key column to a primitive scalar type (STRING, INT, LONG, etc.)
2. If the key must come from a nested field, flatten it upstream with a transform (e.g. FieldMapper/Copy) and use the flattened scalar field as the primary key
3. Cast or convert the key column to STRING in the source SQL/catalog before writing to Elasticsearch

Example fix

// before
primaryKeys = ["user"]  // user is ROW<id INT, name STRING>
// after
primaryKeys = ["user_id"]  // user_id is a scalar STRING/INT field, extracted via transform

for (String pk : primaryKeys) {
    SeaTunnelDataType<?> t = rowType.getFieldType(rowType.indexOf(pk));
    SqlType s = t.getSqlType();
    if (s == SqlType.ROW || s == SqlType.ARRAY || s == SqlType.MAP) {
        throw new IllegalArgumentException("Primary key field '" + pk + "' must be a scalar type, got " + s);
    }
}

boolean isScalarKey(SeaTunnelDataType<?> t) {
    SqlType s = t.getSqlType();
    return s != SqlType.ROW && s != SqlType.ARRAY && s != SqlType.MAP;
}

When it happens

Trigger: Declaring a SeaTunnel table whose primary key (or index/`_id` key) column is of type ROW, ARRAY, or MAP; KeyExtractor.createFieldFormatter throws as soon as it builds the field formatter for that column.

Common situations: Source tables with composite/nested keys mapped to Elasticsearch sinks; CDC rows whose primary key is a struct; users assuming nested fields are flattened automatically for key extraction.

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

• Unsupported type in LocalTimeArrayType: ${eleSqlType}
• Unsupported type: ${sqlType}
• Unsupported type: ${clazz}
• array inject error, unsupported data type: " + type
• UNSUPPORTED_TYPE

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/a910acdb957e7128. Report an issue: GitHub.