Enum datafusion_expr::ColumnarValue

pub enum ColumnarValue {
    Array(ArrayRef),
    Scalar(ScalarValue),
}

Represents the result of evaluating an expression: either a single ScalarValue or an [ArrayRef].

While a ColumnarValue can always be converted into an array for convenience, it is often much more performant to provide an optimized path for scalar values.

Variants

Array(ArrayRef)

Array of values

Scalar(ScalarValue)

A single value

Implementations

impl ColumnarValue

pub fn data_type(&self) -> DataType

pub fn into_array(self, num_rows: usize) -> ArrayRef

Convert a columnar value into an ArrayRef. Self::Scalar is converted by repeating the same scalar multiple times.

pub fn create_null_array(num_rows: usize) -> Self

null columnar values are implemented as a null array in order to pass batch num_rows

Trait Implementations

impl Clone for ColumnarValue

fn clone(&self) -> ColumnarValue

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ColumnarValue

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

Formats the value using the given formatter.