dbt-labs/dbt-core · error

Expected a model node

Error message

Expected a model node

What it means

After the config value successfully deserializes into an InternalDbtNodeWrapper, `dynamic_table_config_changeset` requires it to be the Model variant. Any other node kind (e.g. seed, snapshot, test) hits the catch-all arm and produces this InvalidOperation error. It guards the downstream code that only knows how to build a dynamic-table changeset from a model node.

Solutions

1. Only call dynamic_table_config_changeset from model nodes; remove the call from snapshot/seed contexts.
2. If you need equivalent behavior for another node type, implement a branch for that wrapper variant instead of forcing it through the model path.
3. Confirm the config you passed actually corresponds to the model in question, not another node.

{% if node.resource_type != 'model' %}
  {{ exceptions.warn('dynamic_table_config_changeset is model-only; skipping') }}
{% else %}
  {{ relation.dynamic_table_config_changeset(config) }}
{% endif %}

fn is_model_wrapper(w: &InternalDbtNodeWrapper) -> bool {
    matches!(w, InternalDbtNodeWrapper::Model(_))
}

try:
    relation.dynamic_table_config_changeset(config)
except minijinja.Error as e:
    if 'Expected a model node' in str(e):
        skip_changeset()
    else:
        raise

When it happens

Trigger: Invoking dynamic_table_config_changeset from a non-model node context (snapshot, seed, etc.) whose wrapper deserializes as a variant other than InternalDbtNodeWrapper::Model.

Common situations: Calling this relation method in a snapshot or seed macro, or reusing model relation macros in custom materializations attached to non-model nodes.

Understand the failure class

Background: "is not a compatible type" / "cannot merge" errors: when a value's type doesn't match what the library requires — this error's family across 65 libraries.

Related errors

• adapter not found in context
• adapter should be configured for the parse phase
• compute_external_path: Failed to deserialize config
• compute_external_path: Failed to deserialize…
• describe_dynamic_table is not supported by the

AI-assisted analysis of dbt-labs/dbt-core@0267ce9170 (2026-09-07). Data as JSON: /api/errors/589786bbecf9c447. Report an issue: GitHub.

Appendix: source

Thrown at crates/dbt-adapter/src/relation/relation_impl.rs:1030

        relation_config_value: &Value,
    ) -> Result<Value, minijinja::Error> {
        match self.adapter_type {
            AdapterType::Snowflake => {
                // TODO(serramatutu): minijinja_value_to_typed_struct does not work with references, so we
                // have to clone the value here...
                let local_config = minijinja_value_to_typed_struct::<InternalDbtNodeWrapper>(
                    relation_config_value.clone(),
                )
                .map_err(|e| {
                    minijinja::Error::new(
                        minijinja::ErrorKind::SerdeDeserializeError,
                        format!("Failed to deserialize InternalDbtNodeWrapper: {e}"),
                    )
                })?;
                let local_config = match local_config {
                    InternalDbtNodeWrapper::Model(model) => model,
                    _ => {
                        return Err(minijinja::Error::new(
                            minijinja::ErrorKind::InvalidOperation,
                            "Expected a model node",
                        ));
                    }
                };

                dynamic_table_config_changeset_from_local_config(
                    local_config.as_ref(),
                    relation_results_value,
                )
            }
            _ => Err(minijinja::Error::new(
                minijinja::ErrorKind::InvalidOperation,
                "Only available for snowflake",
            )),
        }
    }

View on GitHub (pinned to 0267ce9170)