Struct DistinctOn

pub struct DistinctOn {
    pub on_expr: Vec<Expr>,
    pub select_expr: Vec<Expr>,
    pub sort_expr: Option<Vec<Sort>>,
    pub input: Arc<LogicalPlan>,
    pub schema: Arc<DFSchema>,
}

Removes duplicate rows from the input

Fields

on_expr: Vec<Expr>

The DISTINCT ON clause expression list

select_expr: Vec<Expr>

The selected projection expression list

sort_expr: Option<Vec<Sort>>

The ORDER BY clause, whose initial expressions must match those of the ON clause when present. Note that those matching expressions actually wrap the ON expressions with additional info pertaining to the sorting procedure (i.e. ASC/DESC, and NULLS FIRST/LAST).

input: Arc<LogicalPlan>

The logical plan that is being DISTINCT’d

schema: Arc<DFSchema>

The schema description of the DISTINCT ON output

Implementations

impl DistinctOn

pub fn try_new( on_expr: Vec<Expr>, select_expr: Vec<Expr>, sort_expr: Option<Vec<Sort>>, input: Arc<LogicalPlan>, ) -> Result<DistinctOn, DataFusionError>

Create a new DistinctOn struct.

pub fn with_sort_expr( self, sort_expr: Vec<Sort>, ) -> Result<DistinctOn, DataFusionError>

Try to update self with a new sort expressions.

Validates that the sort expressions are a super-set of the ON expressions.

Trait Implementations

impl Clone for DistinctOn

fn clone(&self) -> DistinctOn

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for DistinctOn

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

Formats the value using the given formatter.

impl Hash for DistinctOn

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for DistinctOn

fn eq(&self, other: &DistinctOn) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for DistinctOn

fn partial_cmp(&self, other: &DistinctOn) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for DistinctOn

impl StructuralPartialEq for DistinctOn