hasura/graphql-engine · error · BooleanExpressionError::UnknownFieldInObjectBooleanExpressionType

unknown field '{field_name:}' used in object boolean express

Error message

unknown field '{field_name:}' used in object boolean expression type {object_boolean_expression_type:}

What it means

During boolean expression construction, each comparison operator defined on an object boolean expression type must name a real field of the backing object type. This error fires when an operator (or comparable field) references a field name that does not exist on that object type.

Source

Thrown at v3/crates/metadata-resolve/src/stages/boolean_expressions/error.rs:47

        boolean_expression_type_name: Qualified<CustomTypeName>,
        type_name: Qualified<CustomTypeName>,
    },
    #[error(
        "unknown data connector {data_connector:} referenced in object boolean expression type {object_boolean_expression_type:}"
    )]
    UnknownDataConnectorInObjectBooleanExpressionType {
        data_connector: Qualified<DataConnectorName>,
        object_boolean_expression_type: Qualified<CustomTypeName>,
    },
    #[error(
        "unknown data connector object type {data_connector_object_type:} (in data connector {data_connector:}) referenced in object boolean expression type {object_boolean_expression_type:}"
    )]
    UnknownDataConnectorTypeInObjectBooleanExpressionType {
        data_connector: Qualified<DataConnectorName>,
        data_connector_object_type: DataConnectorObjectType,
        object_boolean_expression_type: Qualified<CustomTypeName>,
    },
    #[error(
        "unknown field '{field_name:}' used in object boolean expression type {object_boolean_expression_type:}"
    )]
    UnknownFieldInObjectBooleanExpressionType {
        field_name: FieldName,
        object_boolean_expression_type: Qualified<CustomTypeName>,
    },
    #[error(
        "relationship '{relationship_name}' is used in comparableRelationships in boolean expression type '{object_boolean_expression_type}' does not exist on type '{type_name}'"
    )]
    UnknownRelationshipInObjectBooleanExpressionType {
        relationship_name: RelationshipName,
        object_boolean_expression_type: Qualified<CustomTypeName>,
        type_name: Qualified<CustomTypeName>,
    },
    #[error(
        "the object type '{object_type:}' used in boolean expression type {object_boolean_expression_type:} does not have a mapping to object {data_connector_object_type:} of data connector {data_connector:}"
    )]
    NoDataConnectorTypeMappingForObjectTypeInBooleanExpression {

View on GitHub (pinned to 724551b9ae)

Solutions

  1. Compare the field name in the error against the backing object type's field list
  2. Fix or remove the operator/comparable field entry referencing the unknown field
  3. If the field was renamed, update the boolean expression config to the new name
  4. Rebuild metadata

Example fix

# before
filter:
  operators:
    my_sub.SomeBooleanExpression:
      fields:
      - name: emial   # typo
# after
filter:
  operators:
    my_sub.SomeBooleanExpression:
      fields:
      - name: email
Defensive patterns

Strategy: validation

Validate before calling

// Every operator/comparable field must exist on the backing object type
let fields: HashSet<&str> = object_type.fields().map(|f| f.name()).collect();
for f in boolean_expr.filterable_fields() {
    if !fields.contains(f.as_str()) {
        return Err(format!("field {f} does not exist on backing object type"));
    }
}

Try / catch

match resolve(metadata) {
    Err(BooleanExpressionError::UnknownFieldInObjectBooleanExpressionType { field_name, object_boolean_expression_type }) => {
        // fix or drop the operator referencing field_name
    }
    other => other,
}

Prevention

When it happens

Trigger: Defining filter operators on a boolean expression type that reference field names not present on the backing object type; renaming or removing a field from the object type without updating the boolean expression's operator definitions.

Common situations: Field renames in the object type after filter configuration was authored; typos in field names inside object boolean expression operator config; mismatched casing of field identifiers.

Related errors

AI-assisted analysis of hasura/graphql-engine@724551b9ae (2026-08-28). Data as JSON: /api/errors/c59257f697df7827. Report an issue: GitHub.