Struct datafusion_expr::Projection

#[non_exhaustive]
pub struct Projection {
    pub expr: Vec<Expr>,
    pub input: Arc<LogicalPlan>,
    pub schema: DFSchemaRef,
}

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>

The list of expressions

input: Arc<LogicalPlan>

The incoming logical plan

schema: DFSchemaRef

The schema description of the output

Implementations

impl Projection

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

Create a new Projection

pub fn try_new_with_schema( expr: Vec<Expr>, input: Arc<LogicalPlan>, schema: DFSchemaRef ) -> Result<Self, DataFusionError>

Create a new Projection using the specified output schema

pub fn new_from_schema(input: Arc<LogicalPlan>, schema: DFSchemaRef) -> Self

Create a new Projection using the specified output schema

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

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.