Struct datafusion::logical_expr::Projection

pub struct Projection {
    pub expr: Vec<Expr, Global>,
    pub input: Arc<LogicalPlan>,
    pub schema: Arc<DFSchema>,
}

Evaluates an arbitrary list of expressions (essentially a SELECT with an expression list) on its input.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

expr: Vec<Expr, Global>

The list of expressions

input: Arc<LogicalPlan>

The incoming logical plan

schema: Arc<DFSchema>

The schema description of the output

Implementations

impl Projection

pub fn try_new( expr: Vec<Expr, Global>, input: Arc<LogicalPlan> ) -> Result<Projection, DataFusionError>

Create a new Projection

pub fn try_new_with_schema( expr: Vec<Expr, Global>, input: Arc<LogicalPlan>, schema: Arc<DFSchema> ) -> Result<Projection, DataFusionError>

Create a new Projection using the specified output schema

pub fn new_from_schema( input: Arc<LogicalPlan>, schema: Arc<DFSchema> ) -> Projection

Create a new Projection using the specified output schema

pub fn try_from_plan(plan: &LogicalPlan) -> Result<&Projection, DataFusionError>

Trait Implementations

impl Clone for Projection

fn clone(&self) -> Projection

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Hash for Projection

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<Projection> for Projection

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

This method tests for self and other values to be equal, and is used by ==.

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

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

impl Eq for Projection

impl StructuralEq for Projection

impl StructuralPartialEq for Projection