apache/cassandra · error · InvalidConstraintDefinitionException

There are duplicate constraint definitions on column '%s': %

Error message

There are duplicate constraint definitions on column '%s': %s

What it means

ColumnConstraints.checkSatisfiability detects when the same constraint (same constraint name enabling duplicates) is defined more than once on a single column, which would be ambiguous or redundant. It throws InvalidConstraintDefinitionException listing the column and the duplicated constraint names. This is schema-definition-time validation.

Source

Thrown at src/java/org/apache/cassandra/cql3/constraints/ColumnConstraints.java:194

        public void checkSatisfiability(List<ColumnConstraint<?>> constraints, ColumnMetadata columnMetadata)
        {
            Set<String> constraintNames = new TreeSet<>();
            List<String> duplicateConstraints = new ArrayList<>();

            for (ColumnConstraint<?> constraint : constraints)
            {
                String constraintFullName = constraint.fullName();
                String constraintName = constraint.name();

                if (!constraintNames.add(constraintFullName))
                {
                    if (!constraint.enablesDuplicateDefinitions(constraintName))
                        duplicateConstraints.add(constraintFullName);
                }
            }

            if (!duplicateConstraints.isEmpty())
                throw new InvalidConstraintDefinitionException(format("There are duplicate constraint definitions on column '%s': %s",
                                                                      columnMetadata.name,
                                                                      duplicateConstraints));
        }
    }

    private static class Noop extends ColumnConstraints
    {
        private Noop()
        {
            super(Collections.emptyList());
        }

        @Override
        public void validate(ColumnMetadata columnMetadata)
        {
            // Do nothing. It is always valid
        }

View on GitHub (pinned to 88fd0f6a0e)

Solutions

Remove the duplicate constraint so each constraint appears once per column.
Merge duplicate constraints into a single one covering all needed checks (e.g. combine length bounds into one range).
Use a constraint implementation whose enablesDuplicateDefinitions() returns true if multiple instances are intentional.

Example fix

// before
name text CONSTRAINT CHECK LENGTH(1..10) CONSTRAINT CHECK LENGTH(1..20)
// after
name text CONSTRAINT CHECK LENGTH(1..20)

Defensive patterns

Strategy: validation

Validate before calling

Map<String,Integer> counts = new HashMap<>();
for (ColumnConstraint<?> c : constraints)
    counts.merge(c.name(), 1, Integer::sum);
if (counts.values().stream().anyMatch(n -> n > 1)) throw new IllegalStateException("duplicate constraint definitions");

Prevention

Deduplicate constraint lists in schema-builder code
Idempotent migration scripts: check for existing constraint before adding
Review hand-edited DDL for repeated CHECK clauses

When it happens

Trigger: A CREATE TABLE / ALTER TABLE statement specifies two constraints of the same kind on one column where the constraint's enablesDuplicateDefinitions() returns false — e.g. two identical LENGTH or JSON constraints on the same column.

Common situations: Hand-written DDL that repeats a constraint; schema migration scripts that re-add a constraint already present; generated DDL merging constraint lists without deduplication.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

AI-assisted analysis of apache/cassandra@88fd0f6a0e (2026-09-10). Data as JSON: /api/errors/369d22785f764082. Report an issue: GitHub.