Trait sql::plan::expr::AbstractExpr

pub trait AbstractExpr {
    type Type: AbstractColumnType;
    fn typ(
        &self, 
        outers: &[RelationType], 
        inner: &RelationType, 
        params: &BTreeMap<usize, ScalarType>
    ) -> Self::Type;
}

An expression whose type can be ascertained.

Abstracts over ScalarExpr and CoercibleScalarExpr.

Associated Types

type Type: AbstractColumnType

Required methods

fn typ(
    &self,
    outers: &[RelationType],
    inner: &RelationType,
    params: &BTreeMap<usize, ScalarType>
) -> Self::Type

Computes the type of the expression.

Implementors

impl AbstractExpr for CoercibleScalarExpr

type Type = Option<ColumnType>

impl AbstractExpr for HirScalarExpr

type Type = ColumnType