Method expressions

datafusion/expr/src/logical_plan/plan.rs:413–422

Returns all expressions (non-recursively) evaluated by the current logical plan node. This does not include expressions in any children. Note this method `clone`s all the expressions. When possible, the [`tree_node`] API should be used instead of this API. The returned expressions do not necessarily represent or even contributed to the output schema of this node. For example, `LogicalPlan::Filte

(self: &LogicalPlan)

    ///
    /// [`tree_node`]: crate::logical_plan::tree_node
    pub fn expressions(self: &LogicalPlan) -> Vec<Expr> {
        let mut exprs = vec![];
        self.apply_expressions(|e| {
            exprs.push(e.clone());
            Ok(TreeNodeRecursion::Continue)
        })
        // closure always returns OK
        .unwrap();
        exprs
    }

    /// Returns all the out reference(correlated) expressions (recursively) in the current
    /// logical plan nodes and all its descendant nodes.