Trait datafusion::logical_plan::ExprSchemable

pub trait ExprSchemable {
    fn get_type<S>(&self, schema: &S) -> Result<DataType, DataFusionError>
    where
        S: ExprSchema;
    fn nullable<S>(&self, input_schema: &S) -> Result<bool, DataFusionError>
    where
        S: ExprSchema;
    fn to_field(
        &self,
        input_schema: &DFSchema
    ) -> Result<DFField, DataFusionError>;
    fn cast_to<S>(
        self,
        cast_to_type: &DataType,
        schema: &S
    ) -> Result<Expr, DataFusionError>
    where
        S: ExprSchema;
}

trait to allow expr to typable with respect to a schema

Required Methods

fn get_type<S>(&self, schema: &S) -> Result<DataType, DataFusionError> where
    S: ExprSchema, 

given a schema, return the type of the expr

fn nullable<S>(&self, input_schema: &S) -> Result<bool, DataFusionError> where
    S: ExprSchema, 

given a schema, return the nullability of the expr

fn to_field(&self, input_schema: &DFSchema) -> Result<DFField, DataFusionError>

convert to a field with respect to a schema

fn cast_to<S>(
    self,
    cast_to_type: &DataType,
    schema: &S
) -> Result<Expr, DataFusionError> where
    S: ExprSchema, 

cast to a type with respect to a schema

Implementors

impl ExprSchemable for Expr