Struct Transforms 

pub struct Transforms {
    pub filter: Option<Filter>,
    pub select: Option<Vec<String>>,
    pub rename: Vec<(String, String)>,
    pub limit: Option<usize>,
}

Row-level transformations applied between reading and writing.

Transforms are applied in order: filter → rename → select → limit. All transforms are optional; an empty Transforms is a no-op.

Fields

filter: Option<Filter>

select: Option<Vec<String>>

rename: Vec<(String, String)>

limit: Option<usize>

Implementations

impl Transforms

pub fn is_empty(&self) -> bool

pub fn apply_to_row( &self, row: Vec<(String, CanonicalValue)>, ) -> Option<Vec<(String, CanonicalValue)>>

Applies transforms to a single row. Returns None if the row was filtered out.

pub fn apply_to_array(&self, value: &CanonicalValue) -> CanonicalValue

Applies transforms to a CanonicalValue::Array of objects.

Trait Implementations

impl Clone for Transforms

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Transforms

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

Formats the value using the given formatter.

impl Default for Transforms

fn default() -> Self

Returns the “default value” for a type.