Struct datafusion_optimizer::optimize_projections::OptimizeProjections

pub struct OptimizeProjections {}

A rule for optimizing logical plans by removing unused columns/fields.

OptimizeProjections is an optimizer rule that identifies and eliminates columns from a logical plan that are not used by downstream operations. This can improve query performance and reduce unnecessary data processing.

The rule analyzes the input logical plan, determines the necessary column indices, and then removes any unnecessary columns. It also removes any unnecessary projections from the plan tree.

Implementations

impl OptimizeProjections

pub fn new() -> Self

Trait Implementations

impl Default for OptimizeProjections

fn default() -> OptimizeProjections

Returns the “default value” for a type.

impl OptimizerRule for OptimizeProjections

fn try_optimize( &self, plan: &LogicalPlan, config: &dyn OptimizerConfig ) -> Result<Option<LogicalPlan>>

Try and rewrite plan to an optimized form, returning None if the plan cannot be optimized by this rule.

fn name(&self) -> &str

A human readable name for this optimizer rule

fn apply_order(&self) -> Option<ApplyOrder>

How should the rule be applied by the optimizer? See comments on ApplyOrder for details.