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PatternCost

oxirs_arq::optimizer::join_order

Struct PatternCost 

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pub struct PatternCost {
    pub estimated_cardinality: u64,
    pub selectivity: f64,
    pub bound_count: u8,
}
Expand description

Cost estimate for a single triple pattern.

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§estimated_cardinality: u64

Estimated cardinality of the result set.

§selectivity: f64

Selectivity factor in (0.0, 1.0] — lower is more selective.

§bound_count: u8

Number of bound (non-variable) terms in the pattern (0..=3).

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impl PatternCost

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pub fn ordering_score(&self) -> f64

Composite score used for greedy ordering: lower is better (execute first).

Combines cardinality and selectivity, biased toward patterns with more bound terms.

Trait Implementations§

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impl Clone for PatternCost

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fn clone(&self) -> PatternCost

Returns a duplicate of the value. Read more
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fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for PatternCost

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

Formats the value using the given formatter. Read more

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