What causes "map is not supported yet" in risingwavelabs/risingwave?

Restructure the data as a STRUCT type, which the sink handles as a DynamoDB map (AttributeValue::M) via nested map_data.

risingwavelabs/risingwave · error · SinkError::DynamoDb

map is not supported yet

Error message

map is not supported yet

What it means

Sentinel error in the DynamoDB sink's map_data conversion: a DataType::Map datum was encountered while translating a row into DynamoDB AttributeValues, and Map is not among the supported data types. The sink cannot yet represent map-typed columns; remove the map column or change its type.

Source

Thrown at src/connector/src/sink/dynamodb.rs:389

                .iter()
                .map(|x| map_data(x, lt.elem()))
                .collect::<Result<Vec<_>>>()?;
            AttributeValue::L(list_attr)
        }
        DataType::Struct(st) => {
            let mut map = HashMap::with_capacity(st.len());
            for (sub_datum_ref, (name, data_type)) in scalar_ref
                .into_struct()
                .iter_fields_ref()
                .zip_eq_debug(st.iter())
            {
                let attr = map_data(sub_datum_ref, data_type)?;
                map.insert(name.to_owned(), attr);
            }
            AttributeValue::M(map)
        }
        DataType::Map(_m) => {
            return Err(SinkError::DynamoDb(anyhow!("map is not supported yet")));
        }
        DataType::Vector(_) => {
            return Err(SinkError::DynamoDb(anyhow!("vector is not supported yet")));
        }
    };
    Ok(attr)
}

fn rw_pk_names(schema: &Schema, pk_indices: &[usize]) -> Result<Vec<String>> {
    pk_indices
        .iter()
        .map(|pk_idx| {
            schema
                .fields()
                .get(*pk_idx)
                .map(|field| field.name.clone())
                .ok_or_else(|| {
                    SinkError::DynamoDb(anyhow!(

View on GitHub (pinned to 6469eb736d)

Solutions

Restructure the data as a STRUCT type, which the sink handles as a DynamoDB map (AttributeValue::M) via nested map_data.
Convert the MAP to JSONB (e.g. via cast) so it is serialized as a string attribute.
Sink flattened key/value columns instead of a single MAP column.
Track/await MAP support in the DynamoDB sink connector.

Example fix

// before
CREATE MATERIALIZED VIEW mv AS SELECT attrs::MAP<VARCHAR,VARCHAR> AS attrs FROM src;
// after: use struct or jsonb
CREATE MATERIALIZED VIEW mv AS SELECT attrs::JSONB AS attrs FROM src;

Defensive patterns

Strategy: validation

Validate before calling

-- ensure no MAP columns before sinking to DynamoDB
SELECT count(*) FROM rw_catalog.rw_columns WHERE relation_id = <mv_id> AND data_type LIKE 'MAP%';

Prevention

Model nested data as STRUCT (supported) rather than MAP.
Cast MAP columns to JSONB in the sink's upstream view.
Review relation schema for unsupported types before creating DynamoDB sinks.

When it happens

Trigger: Any row containing a MAP-typed column flows into a table that is sunk to DynamoDB (via format_row -> map_data).

Common situations: Sources with map/struct-like data mapped to RisingWave MAP columns, then sunk directly to DynamoDB; schema evolution introducing a MAP column to an already-sunk relation.

Understand the failure class

Background: UnsupportedOperationException and "is not supported" errors: when a library deliberately refuses a call — this error's family across 30 libraries.

Related errors

AI-assisted analysis of risingwavelabs/risingwave@6469eb736d (2026-09-11). Data as JSON: /api/errors/f7a645fb552fd1aa. Report an issue: GitHub.