Function sql::plan::query::cast_relation

fn cast_relation<'a, I>(
    qcx: &QueryContext<'_>, 
    ccx: CastContext, 
    expr: HirRelationExpr, 
    target_types: I
) -> Result<HirRelationExpr, CastRelationError> where
    I: IntoIterator<Item = &'a ScalarType>, 

Cast a relation from one type to another using the specified type of cast.

The length of target_types must match the arity of expr.