Struct Plan 

pub struct Plan {
    pub stages: Vec<Stage>,
    pub budget: Option<usize>,
    pub refusals: Vec<String>,
}

What ran, in the order it ran.

Fields

stages: Vec<Stage>

budget: Option<usize>

Set when the row budget let a stage stop before consuming its input.

refusals: Vec<String>

Why the optimiser declined to push a predicate. Recorded rather than silent: you cannot tell “correctly refused” from “forgot to look” if the decision leaves no trace.

Implementations

impl Plan

pub fn push(&mut self, s: Stage)

pub fn joins(&self) -> Vec<&Stage>

The join stages, for callers that only care how joins were executed.

Keeps the differential tests and the benchmark reading the same report the plan is built from, rather than a second source of truth.

pub fn join_strategy(&self, n: usize) -> Option<Strategy>

The strategy of the nth join, if there is one.

pub fn join_strategies(&self) -> Vec<Strategy>

The strategy of every join, in execution order.

pub fn join_keys(&self, n: usize) -> Option<usize>

Proven equality key count of the nth join.

pub fn tree(&self) -> Option<PlanTree>

The pipeline as a tree. None when nothing ran (SELECT 1).

Stages are recorded as: the base scan, then per join its right-hand scan followed by the join itself, then the postfix stages. That shape is what makes the reconstruction unambiguous.

pub fn render(&self) -> Vec<String>

Render as EXPLAIN output: one string per line, innermost first, the way PostgreSQL nests its plan tree.

The pipeline is linear, so indentation grows monotonically. A reader familiar with PostgreSQL’s output will read this correctly; a reader who is not still sees the order things happened in.

Trait Implementations

impl Clone for Plan

fn clone(&self) -> Plan

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Plan

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for Plan

fn default() -> Plan

Returns the “default value” for a type.

impl Eq for Plan

impl PartialEq for Plan

fn eq(&self, other: &Plan) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Plan