apache/cassandra · error · MarshalException

Unable to make boolean from '%s'

Error message

Unable to make boolean from '%s'

What it means

BooleanType.fromString throws this when the input string is neither 'true' nor 'false' (case-insensitive). Cassandra's boolean parser accepts only these two literals; anything else (including '1', 'yes', or values with stray whitespace) is rejected. The failing string is included in the message.

Source

Thrown at src/java/org/apache/cassandra/db/marshal/BooleanType.java:93

    @Override
    public <V> V fromComparableBytes(ValueAccessor<V> accessor, ByteSource.Peekable comparableBytes, ByteComparable.Version version)
    {
        if (comparableBytes == null)
            return accessor.empty();
        int b = comparableBytes.next();
        return accessor.valueOf(b == 1);
    }

    public ByteBuffer fromString(String source) throws MarshalException
    {

        if (source.isEmpty()|| source.equalsIgnoreCase(Boolean.FALSE.toString()))
            return decompose(false);

        if (source.equalsIgnoreCase(Boolean.TRUE.toString()))
            return decompose(true);

        throw new MarshalException(String.format("Unable to make boolean from '%s'", source));
    }

    @Override
    public Term fromJSONObject(Object parsed) throws MarshalException
    {
        if (parsed instanceof String)
            return new Constants.Value(fromString((String) parsed));
        else if (!(parsed instanceof Boolean))
            throw new MarshalException(String.format(
                    "Expected a boolean value, but got a %s: %s", parsed.getClass().getSimpleName(), parsed));

        return new Constants.Value(getSerializer().serialize((Boolean) parsed));
    }

    @Override
    public String toJSONString(ByteBuffer buffer, ProtocolVersion protocolVersion)
    {
        return getSerializer().deserialize(buffer).toString();

View on GitHub (pinned to 88fd0f6a0e)

Solutions

1. Use the exact literals true or false (any case, no extra whitespace)
2. Convert 0/1 or yes/no to true/false in the import/ETL layer
3. If column holds numeric flags, change type to tinyint and store 0/1
4. Trim and normalize the value before binding: value.trim().toLowerCase()

Example fix

// before
INSERT INTO t (k, flag) VALUES (1, 'yes');
// after
INSERT INTO t (k, flag) VALUES (1, true);

public static void assertBooleanLiteral(String s) {
    String t = s == null ? null : s.trim().toLowerCase();
    if (!"true".equals(t) && !"false".equals(t))
        throw new IllegalArgumentException("Not a boolean literal: " + s);
}

When it happens

Trigger: INSERT with '1'/'yes'/'on' or whitespace-padded variants into a boolean column via the fromString path; fromJSONObject with a string that is not true/false; localized boolean representations (e.g. 'vrai').

Common situations: Data imported from CSVs using 0/1 or yes/no conventions; config-driven inserts where booleans render with trailing whitespace; shell env vars carrying '1' for boolean flags.

Understand the failure class

Background: "Invalid ... format", "must be in format X", "does not look like a ..." — invalid argument format errors across CLI tools and libraries — this error's family across 17 libraries.

Related errors

• Expected a boolean value, but got a %s: %s
• Unable to make short from '%s'
• Cannot parse 32-bits int value from "%s"
• Cannot parse timestamp value from "%s"
• Cannot parse date value from "%s"

AI-assisted analysis of apache/cassandra@88fd0f6a0e (2026-09-10). Data as JSON: /api/errors/639638d9cea15147. Report an issue: GitHub.