apache/cassandra · error · InvalidRequestException

Must provide at least one partition key column for…

Error message

Must provide at least one partition key column for materialized view '%s'

What it means

A materialized view must define its own primary key, which requires at least one partition key column. An empty PARTITION KEY / PRIMARY KEY clause leaves the view without a partitioner, so creation is rejected.

Solutions

Explicitly include at least one column in the view's PARTITION KEY, e.g. PRIMARY KEY (pk, ck)
Ensure the listed partition key columns also appear in the SELECT list (they are usually required in the WHERE IS NOT NULL clauses too)

Example fix

// before
CREATE MATERIALIZED VIEW mv AS SELECT ck, v FROM base WHERE ck IS NOT NULL PRIMARY KEY (( ) , ck);
// after
CREATE MATERIALIZED VIEW mv AS SELECT pk, ck, v FROM base WHERE pk IS NOT NULL AND ck IS NOT NULL PRIMARY KEY (pk, ck);

Defensive patterns

Strategy: validation

Validate before calling

if (partitionKeyCols.isEmpty()) throw new IllegalArgumentException("MV needs at least one partition key column");

Try / catch

try { session.execute(createMvStmt); } catch (InvalidQueryException e) { if (e.getMessage().contains("at least one partition key")) { /* fix PRIMARY KEY clause */ } }

Prevention

Always write PRIMARY KEY with a non-empty partition-key section, e.g. ((pk), ck)
Validate generated DDL with a parser before execution

When it happens

Trigger: CREATE MATERIALIZED VIEW ... PRIMARY KEY (() , ck) or omitted partition key columns such that partitionKeyColumns is empty at validation.

Common situations: Syntax mistakes in the PRIMARY KEY clause (parenthesization leaving the partition key empty); assuming the base partition key is inherited automatically.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

AI-assisted analysis of apache/cassandra@88fd0f6a0e (2026-09-10). Data as JSON: /api/errors/1a619ebc5b48d821. Report an issue: GitHub.

Appendix: source

Thrown at src/java/org/apache/cassandra/cql3/statements/schema/CreateViewStatement.java:238

            // will throw IRE if the column doesn't exist in the base table
            Selectable.RawIdentifier rawIdentifier = (Selectable.RawIdentifier) selector.selectable;
            ColumnMetadata column = rawIdentifier.columnMetadata(table);

            selectedColumns.add(column.name);
        });

        selectedColumns.stream()
                       .map(table::getColumn)
                       .filter(ColumnMetadata::isStatic)
                       .findAny()
                       .ifPresent(c -> { throw ire("Cannot include static column '%s' in materialized view '%s'", c, viewName); });

        /*
         * Process PRIMARY KEY columns and CLUSTERING ORDER BY clause
         */

        if (partitionKeyColumns.isEmpty())
            throw ire("Must provide at least one partition key column for materialized view '%s'", viewName);

        HashSet<ColumnIdentifier> primaryKeyColumns = new HashSet<>();

        concat(partitionKeyColumns, clusteringColumns).forEach(name ->
        {
            ColumnMetadata column = table.getColumn(name);
            if (null == column || !selectedColumns.contains(name))
                throw ire("Unknown column '%s' referenced in PRIMARY KEY for materialized view '%s'", name, viewName);

            if (!primaryKeyColumns.add(name))
                throw ire("Duplicate column '%s' in PRIMARY KEY clause for materialized view '%s'", name, viewName);

            AbstractType<?> type = column.type;

            if (type.isMultiCell())
            {
                if (type.isCollection())
                    throw ire("Invalid non-frozen collection type '%s' for PRIMARY KEY column '%s'", type, name);

View on GitHub (pinned to 88fd0f6a0e)