Method join_scalars

src/expr/src/relation.rs:1308–1320

Constructs a join operator from inputs and required-equal scalar expressions.

(
        mut inputs: Vec<MirRelationExpr>,
        equivalences: Vec<Vec<MirScalarExpr>>,
    )

    /// Constructs a join operator from inputs and required-equal scalar expressions.
    pub fn join_scalars(
        mut inputs: Vec<MirRelationExpr>,
        equivalences: Vec<Vec<MirScalarExpr>>,
    ) -> Self {
        // Remove all constant inputs that are the identity for join.
        // They neither introduce nor modify any column references.
        inputs.retain(|i| !i.is_constant_singleton());
        MirRelationExpr::Join {
            inputs,
            equivalences,
            implementation: JoinImplementation::Unimplemented,
        }
    }

    /// Perform a key-wise reduction / aggregation.
    ///