Trait rusqlite::functions::WindowAggregate

pub trait WindowAggregate<A, T>: Aggregate<A, T> where
    A: RefUnwindSafe + UnwindSafe,
    T: ToSql, {
    fn value(&self, _: Option<&A>) -> Result<T>;
    fn inverse(&self, _: &mut Context<'_>, _: &mut A) -> Result<()>;
}

Available on crate features functions and window only.

WindowAggregate is the callback interface for user-defined aggregate window function.

Required Methods

fn value(&self, _: Option<&A>) -> Result<T>

Returns the current value of the aggregate. Unlike xFinal, the implementation should not delete any context.

fn inverse(&self, _: &mut Context<'_>, _: &mut A) -> Result<()>

Removes a row from the current window.

Implementors