apache/cassandra · error · InvalidRequestException

ANN ordering does not support any other ordering

Error message

ANN ordering does not support any other ordering

What it means

A single ANN ordering cannot be combined with any other ORDER BY expression (clustering order or another column ordering). When one non-clustered (ANN) ordering exists alongside other orderings, the statement is rejected.

Source

Thrown at src/java/org/apache/cassandra/cql3/restrictions/StatementRestrictions.java:553

    /**
     * This is a hack to push ordering down to indexes.
     * Indexes are selected based on RowFilter only, so we need to turn orderings into restrictions
     * so they end up in the row filter.
     *
     * @param orderings orderings from the select statement
     * @return the {@link RestrictionSet} with the added orderings
     */
    private RestrictionSet addOrderingRestrictions(List<Ordering> orderings, RestrictionSet restrictionSet)
    {
        List<Ordering> annOrderings = orderings.stream().filter(o -> o.expression.hasNonClusteredOrdering()).collect(Collectors.toList());

        if (annOrderings.size() > 1)
            throw new InvalidRequestException("Cannot specify more than one ANN ordering");
        else if (annOrderings.size() == 1)
        {
            if (orderings.size() > 1)
                throw new InvalidRequestException("ANN ordering does not support any other ordering");
            Ordering annOrdering = annOrderings.get(0);
            if (annOrdering.direction != Ordering.Direction.ASC)
                throw new InvalidRequestException("Descending ANN ordering is not supported");
            SingleRestriction restriction = annOrdering.expression.toRestriction();
            return restrictionSet.addRestriction(restriction);
        }
        return restrictionSet;
    }

    private void processPartitionKeyRestrictions(ClientState state, boolean hasQueriableIndex, boolean allowFiltering, boolean forView)
    {
        if (!type.allowPartitionKeyRanges())
        {
            checkFalse(partitionKeyRestrictions.isOnToken(),
                       "The token function cannot be used in WHERE clauses for %s statements", type);

            if (partitionKeyRestrictions.hasUnrestrictedPartitionKeyComponents())
                throw invalidRequest("Some partition key parts are missing: %s",

View on GitHub (pinned to 88fd0f6a0e)

Solutions

1. Remove the extra ORDER BY column and sort/tie-break results in the application.
2. Issue the ANN-only query and post-process client-side with the secondary sort.
3. If secondary sort semantics are required, restrict the result set first and sort in memory.

Example fix

// before
SELECT * FROM items ORDER BY ann_of(vec) : [0.1,0.2], created_at DESC;
// after
SELECT * FROM items ORDER BY ann_of(vec) : [0.1,0.2]; // sort by created_at client-side

if (hasAnnOrdering(orderings) && orderings.size() > 1)
    throw new IllegalArgumentException("ANN ordering cannot be combined with other orderings");

try { session.execute(stmt); }
catch (InvalidRequestException e) {
    if (e.getMessage().equals("ANN ordering does not support any other ordering")) { /* strip secondary ORDER BY, sort client-side */ }
    else throw e;
}

When it happens

Trigger: SELECT ... FROM table WHERE ... ORDER BY ann_of(v) : [...], some_clustering_col ASC — an ANN ordering plus any additional ordering in the same query.

Common situations: Users expect vector search results sorted first by similarity then by clustering column (tie-breaking) and add both orderings; vector search in Cassandra does not support secondary sort within the ANN scan.

Understand the failure class

Background: Conflicting config options: "cannot be used together" — configuration validation errors across open-source libraries — this error's family across 162 libraries.

Related errors

• Cannot specify more than one ANN ordering
• Descending ANN ordering is not supported
• Unsupported expression during ANN index query:
• %s cannot be restricted by more than one relation in an ANN
• ANN ordering is only supported on float vector indexes

AI-assisted analysis of apache/cassandra@88fd0f6a0e (2026-09-10). Data as JSON: /api/errors/ec4d33121b5b936f. Report an issue: GitHub.