prestodb/presto · error · DataTypeMismatchException

DATATYPE_MISMATCH

DATATYPE_MISMATCH

Error message

Mismatched types: %s vs %s

What it means

EquatableValueSet.checkCompatibility requires that set operations are performed against another ValueSet of the same Presto Type and the same EquatableValueSet implementation; a Type mismatch throws DataTypeMismatchException, and a wrong implementation throws IllegalStateException (separate message).

Source

Thrown at presto-common/src/main/java/com/facebook/presto/common/predicate/EquatableValueSet.java:293

    }

    private static <T> Set<T> union(Set<T> set1, Set<T> set2)
    {
        return Stream.concat(set1.stream(), set2.stream())
                .collect(toLinkedSet());
    }

    private static <T> Set<T> subtract(Set<T> set1, Set<T> set2)
    {
        return set1.stream()
                .filter(value -> !set2.contains(value))
                .collect(toLinkedSet());
    }

    private EquatableValueSet checkCompatibility(ValueSet other)
    {
        if (!getType().equals(other.getType())) {
            throw new DataTypeMismatchException(String.format("Mismatched types: %s vs %s", getType(), other.getType()));
        }
        if (!(other instanceof EquatableValueSet)) {
            throw new IllegalStateException(String.format("ValueSet is not a EquatableValueSet: %s", other.getClass()));
        }
        return (EquatableValueSet) other;
    }

    @Override
    public int hashCode()
    {
        return Objects.hash(type, whiteList, entries);
    }

    @Override
    public boolean equals(Object obj)
    {
        if (this == obj) {
            return true;

View on GitHub (pinned to 55bb57d202)

Solutions

1. Ensure both sets have equal Type before combining; coerce one side if needed
2. Build both sets via ValueSet.of(type, ...) with identical Type instances
3. Key any ValueSet/Domain caches by (column, type) not just column
4. Pre-check with setA.getType().equals(setB.getType()) and handle mismatch explicitly

Example fix

// before
ValueSet merged = varcharSet.union(intSet); // throws
// after
if (varcharSet.getType().equals(intSet.getType())) {
    ValueSet merged = varcharSet.union(intSet);
}

if (!a.getType().equals(b.getType())) {
    throw new IllegalArgumentException("ValueSet type mismatch: " + a.getType() + " vs " + b.getType());
}
ValueSet merged = a.union(b);

try { return a.union(b); } catch (DataTypeMismatchException e) { /* treat as incompatible predicates; widen to none/all */ }

When it happens

Trigger: Calling union/intersect/overlaps/contains via otherValueSet with a ValueSet of a different Type, e.g. combining a VARCHAR EquatableValueSet with an INTEGER one.

Common situations: Merging discrete value sets from different columns or mismatched partition key types; predicate translation bugs in connectors; caching ValueSets keyed only by column name after a type change.

Related errors

• DATATYPE_MISMATCH
• DATATYPE_MISMATCH
• Value class %s does not match required Type class %s
• DRUID_PUSHDOWN_UNSUPPORTED_EXPRESSION

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/3208db0c9bed1519. Report an issue: GitHub.