Struct OptimizeUnions 

pub struct OptimizeUnions;

An optimization rule that

1. replaces nested unions with a single union.
2. removes unions with a single input.

Implementations

impl OptimizeUnions

pub fn new() -> Self

Trait Implementations

impl Debug for OptimizeUnions

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

Formats the value using the given formatter.

impl Default for OptimizeUnions

fn default() -> OptimizeUnions

Returns the “default value” for a type.

impl OptimizerRule for OptimizeUnions

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.

fn supports_rewrite(&self) -> bool

👎Deprecated since 47.0.0: This method is no longer used

Does this rule support rewriting owned plans (rather than by reference)?

fn rewrite( &self, plan: LogicalPlan, _config: &dyn OptimizerConfig, ) -> Result<Transformed<LogicalPlan>>

Try to rewrite plan to an optimized form, returning Transformed::yes if the plan was rewritten and Transformed::no if it was not.