apache/cassandra · error · InvalidRequestException

Duplicate column ' ' in CLUSTERING ORDER BY clause for view

Error message

Duplicate column '%s' in CLUSTERING ORDER BY clause for view '%s'

What it means

Guard in CreateViewStatement.RawStatement.extendClusteringOrder() (parser-side builder): CLUSTERING ORDER BY names the same column twice. clusteringOrder is a map keyed by column identifier, and put() returning a previous value signals the duplicate; the statement is rejected with InvalidRequestException before schema application.

Solutions

List each column at most once in the CLUSTERING ORDER BY clause; remove the redundant entry, since unspecified clustering columns default to ascending order.

Example fix

// before
WITH CLUSTERING ORDER BY (ts ASC, ts DESC)
// after
WITH CLUSTERING ORDER BY (ts ASC)

Defensive patterns

Strategy: validation

Validate before calling

const cols = order.map(o => o.column); if (new Set(cols).size !== cols.length) throw new Error('Duplicate column in CLUSTERING ORDER BY');

Try / catch

try { session.execute(ddl); } catch (e) { if (e instanceof InvalidQueryError && /Duplicate column/.test(e.message)) { /* deduplicate ORDER BY list */ } else throw e; }

Prevention

Deduplicate clustering columns when programmatically assembling ORDER BY clauses
Review generated DDL output before execution

When it happens

Trigger: CREATE MATERIALIZED VIEW ... WITH CLUSTERING ORDER BY (col ASC, col DESC) or any duplicate column listed twice in the ORDER BY clause.

Common situations: Programmatic view builders appending the same column twice; hand-written DDL repeating a column with different directions; generated DDL merging two order specs.

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/feaba3f5fb41f886. Report an issue: GitHub.

Appendix: source

Thrown at src/java/org/apache/cassandra/cql3/statements/schema/CreateViewStatement.java:492

                                           attrs,

                                           ifNotExists);
        }

        public void setPartitionKeyColumns(List<ColumnIdentifier> columns)
        {
            partitionKeyColumns = columns;
        }

        public void markClusteringColumn(ColumnIdentifier column)
        {
            clusteringColumns.add(column);
        }

        public void extendClusteringOrder(ColumnIdentifier column, boolean ascending)
        {
            if (null != clusteringOrder.put(column, ascending))
                throw ire("Duplicate column '%s' in CLUSTERING ORDER BY clause for view '%s'", column, viewName);
        }
    }
}

View on GitHub (pinned to 88fd0f6a0e)