prestodb/presto · error · IllegalStateException

Cannot parse distinct type definition(%s), expected ',' afte

Error message

Cannot parse distinct type definition(%s), expected ',' after position %s

What it means

Thrown by DistinctTypeParsingData.parse when the serialized distinct type signature lacks the first ", " separator after the '{' that opens the definition. The parser expects 'name{baseType, ...' and cannot find the comma following the base type. It indicates a malformed distinct-type signature string.

Source

Thrown at presto-common/src/main/java/com/facebook/presto/common/type/TypeSignature.java:321

            this.distinctType = distinctType;
        }

        private static Optional<QualifiedObjectName> parseParentName(String s)
        {
            return s.equals("null") ? Optional.empty() : Optional.of(QualifiedObjectName.valueOf(s));
        }

        private static DistinctTypeParsingData parse(String signature, int startIndex)
        {
            int openBracketIndex = signature.indexOf("{", startIndex);
            if (openBracketIndex == -1) {
                throw new IllegalStateException(format("Cannot parse distinct type definition(%s), expected '{' after position %s", signature, startIndex));
            }
            QualifiedObjectName name = QualifiedObjectName.valueOf(signature.substring(startIndex, openBracketIndex));

            int firstCommaIndex = signature.indexOf(", ", openBracketIndex);
            if (firstCommaIndex == -1) {
                throw new IllegalStateException(format("Cannot parse distinct type definition(%s), expected ',' after position %s", signature, openBracketIndex));
            }
            TypeSignature baseType = TypeSignature.parseTypeSignature(signature.substring(openBracketIndex + 1, firstCommaIndex));

            int secondCommaIndex = signature.indexOf(", ", firstCommaIndex + 2);
            if (secondCommaIndex == -1) {
                throw new IllegalStateException(format("Cannot parse distinct type definition(%s), expected ',' after position %s", signature, secondCommaIndex));
            }
            boolean isOrderable = parseBoolean(signature.substring(firstCommaIndex + 2, secondCommaIndex));

            int thirdCommaIndex = signature.indexOf(", [", secondCommaIndex + 2);
            if (thirdCommaIndex == -1) {
                throw new IllegalStateException(format("Cannot parse distinct type definition(%s), expected '[' after position %s", signature, secondCommaIndex));
            }
            Optional<QualifiedObjectName> topMostAncestor = parseParentName(signature.substring(secondCommaIndex + 2, thirdCommaIndex));

            int endIndex = signature.indexOf("]}", thirdCommaIndex + 3);
            int position = thirdCommaIndex + 3;
            List<QualifiedObjectName> otherAncestors = new ArrayList<>();

View on GitHub (pinned to 55bb57d202)

Solutions

1. Ensure the signature contains all three fields separated by exactly ', ' (comma + space): 'name{baseType, orderable, [ancestors]}'.
2. Regenerate the signature via TypeSignature.toString() instead of writing it by hand.
3. If separators differ (e.g. ',' without space), fix the serializer; the parser requires the ", " substring.

Example fix

// before
"shop.customer_id{bigint,true,[]}"   // no ', ' separators
// after
"shop.customer_id{bigint, true, []}"

// require ', ' separators between fields
if (!signature.contains("{")) throw new IllegalArgumentException("missing '{' in: " + signature);
int open = signature.indexOf('{');
if (!signature.substring(open).contains(", ")) {
    throw new IllegalArgumentException("distinct type signature missing ', ' separators: " + signature);
}

static boolean hasCommaSpaceSeparators(String sig) {
    if (sig == null) return false;
    int open = sig.indexOf('{');
    return open >= 0 && sig.indexOf(", ", open) > 0;
}

try {
    TypeSignature.parseTypeSignature(signature);
} catch (IllegalStateException e) {
    if (e.getMessage().contains("expected ','")) {
        // regenerate from canonical serialization or reject input
    } else throw e;
}

When it happens

Trigger: Parsing a distinct type signature where the base type is not followed by ', ' — e.g. 'name{bigint true, []}' or 'name{bigint}' with the orderable/ancestors fields missing entirely.

Common situations: Manually constructing signatures for tests, a signature truncated after the base type, connectors or plugins that serialize distinct types with a non-standard separator (e.g. single comma without space — the parser searches for ", " exactly).

Related errors

• Cannot parse distinct type definition(%s), expected '{' afte
• Cannot parse distinct type definition(%s), expected '[' afte
• Bad type signature: '%s'
• Unexpected varchar value in numeric enum signature
• Cannot parse enum signature

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/2a37e7852c9f4754. Report an issue: GitHub.