Enum PropertySource 

#[non_exhaustive]
pub enum PropertySource {
    Column(usize),
    Constant(Value),
    PropertyAccess {
        column: usize,
        property: String,
    },
    Expression {
        expr: Box<FilterExpression>,
        variable_columns: HashMap<String, usize>,
    },
}

Source for a property value.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Column(usize)

Get value from an input column.

Constant(Value)

Use a constant value.

PropertyAccess

Access a named property from a map/node/edge in an input column.

Fields

column: usize

The column containing the map, node ID, or edge ID.

property: String

The property name to extract.

Expression

A runtime expression that may reference a variable not present in the caller’s input chunk. Used by MERGE ... ON CREATE/MATCH SET so that expressions like coalesce(c.description, 'fallback') can reference the MERGE variable, which only exists after the merge resolves.

Generic operators do not know how to evaluate this variant: the default resolve implementation returns Value::Null. Operators that produce an augmented row (e.g., MERGE) must intercept this variant before calling resolve.

Fields

expr: Box<FilterExpression>

The expression to evaluate against an augmented row.

variable_columns: HashMap<String, usize>

Variable-name to column-index map for the augmented row layout.

Implementations

impl PropertySource

pub fn resolve( &self, chunk: &DataChunk, row: usize, store: &dyn GraphStore, ) -> Value

Resolves a property value from a data chunk row.

Returns Value::Null for PropertySource::Expression: those sources require an operator-specific augmented row and must be intercepted by the producing operator (currently the MERGE node and edge operators).

Trait Implementations

impl Clone for PropertySource

fn clone(&self) -> PropertySource

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for PropertySource

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.