prestodb/presto · error · PrestoException

DECODER_CONVERSION_NOT_SUPPORTED

DECODER_CONVERSION_NOT_SUPPORTED

Error message

could not parse non-value node as '%s' for column '%s'

What it means

DefaultJsonFieldDecoder.getBoolean only supports scalar JSON value nodes; it reads value.asBoolean(). If the mapped node is a container (object/array) or missing/non-value node, it throws PrestoException DECODER_CONVERSION_NOT_SUPPORTED. This means the JSON structure does not match the declared boolean column.

Source

Thrown at presto-record-decoder/src/main/java/com/facebook/presto/decoder/json/DefaultJsonFieldDecoder.java:131

            this.value = value;
            this.columnHandle = columnHandle;
            this.minValue = minValue;
            this.maxValue = maxValue;
        }

        @Override
        public final boolean isNull()
        {
            return value.isMissingNode() || value.isNull();
        }

        @Override
        public boolean getBoolean()
        {
            if (value.isValueNode()) {
                return value.asBoolean();
            }
            throw new PrestoException(
                    DECODER_CONVERSION_NOT_SUPPORTED,
                    format("could not parse non-value node as '%s' for column '%s'", columnHandle.getType(), columnHandle.getName()));
        }

        @Override
        public long getLong()
        {
            try {
                long longValue;
                if (value.isIntegralNumber() && !value.isBigInteger()) {
                    longValue = value.longValue();
                    if (longValue >= minValue && longValue <= maxValue) {
                        return longValue;
                    }
                }
                else if (value.isValueNode()) {
                    longValue = parseLong(value.asText());
                    if (longValue >= minValue && longValue <= maxValue) {

View on GitHub (pinned to 55bb57d202)

Solutions

1. Inspect the raw JSON at the mapped field to confirm it is a scalar boolean
2. Fix the column mapping (mapping/dataFormat) to point at a boolean-valued field
3. Adjust producer schema to emit a boolean for this field
4. Remove or retype the column if the field legitimately holds complex JSON

Example fix

// before (row)
{"flag":{"value":true}} mapped to column flag:boolean
// after
{"flag":true} or remap the column to flag.value

boolean ok = jsonNode.path(fieldName).isBoolean();

static boolean isBooleanField(JsonNode n) { return n != null && n.isValueNode() && n.isBoolean(); }

try { boolean b = decoder.getBoolean(); } catch (PrestoException e) { if (e.getErrorCode().getName().equals("DECODER_CONVERSION_NOT_SUPPORTED")) { handleBadRow(); } else throw e; }

When it happens

Trigger: A boolean column mapped to a JSON field whose node is an object or array (isValueNode() false), e.g. the field holds nested JSON instead of true/false.

Common situations: Misconfigured JSON path/column mapping pointing at a nested object; producers switched from boolean to object payloads; schema drift between topic and table definition.

Related errors

• ELASTICSEARCH_TYPE_MISMATCH
• DECODER_CONVERSION_NOT_SUPPORTED
• DECODER_CONVERSION_NOT_SUPPORTED
• Invalid array block:
• Invalid map block:

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/589aa2ae2fdd0706. Report an issue: GitHub.