Method qualified_name

datafusion/expr/src/expr.rs:1616–1626

Returns the qualifier and the schema name of this expression. Used when the expression forms the output field of a certain plan. The result is the field's qualifier and field name in the plan's output schema. We can use this qualified name to reference the field.

(&self)

    /// The result is the field's qualifier and field name in the plan's
    /// output schema. We can use this qualified name to reference the field.
    pub fn qualified_name(&self) -> (Option<TableReference>, String) {
        match self {
            Expr::Column(Column {
                relation,
                name,
                spans: _,
            }) => (relation.clone(), name.clone()),
            Expr::Alias(Alias { relation, name, .. }) => (relation.clone(), name.clone()),
            _ => (None, self.schema_name().to_string()),
        }
    }

    /// Returns placement information for this expression.
    ///