datafusion-functions-aggregate-common 48.0.0

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/// Represents the sensitivity of an aggregate expression to ordering.
#[derive(Debug, PartialEq, Eq, Clone, Copy)]
pub enum AggregateOrderSensitivity {
    /// Indicates that the aggregate expression is insensitive to ordering.
    /// Ordering at the input is not important for the result of the aggregator.
    Insensitive,
    /// Indicates that the aggregate expression has a hard requirement on ordering.
    /// The aggregator can not produce a correct result unless its ordering
    /// requirement is satisfied.
    HardRequirement,
    /// Indicates that ordering is beneficial for the aggregate expression in terms
    /// of evaluation efficiency. The aggregator can produce its result efficiently
    /// when its required ordering is satisfied; however, it can still produce the
    /// correct result (albeit less efficiently) when its required ordering is not met.
    Beneficial,
}

impl AggregateOrderSensitivity {
    pub fn is_insensitive(&self) -> bool {
        self.eq(&AggregateOrderSensitivity::Insensitive)
    }

    pub fn is_beneficial(&self) -> bool {
        self.eq(&AggregateOrderSensitivity::Beneficial)
    }

    pub fn hard_requires(&self) -> bool {
        self.eq(&AggregateOrderSensitivity::HardRequirement)
    }
}