CountFunction

sql_cli::sql::aggregates::functions

Struct CountFunction

pub struct CountFunction;

Expand description

COUNT(column) - counts non-null values

Trait Implementations§

impl AggregateFunction for CountFunction

fn name(&self) -> &'static str

Name of the function (e.g., “SUM”, “AVG”)

fn init(&self) -> AggregateState

Initialize the aggregation state

fn accumulate( &self, state: &mut AggregateState, value: &DataValue, ) -> Result<()>

Add a value to the aggregation

fn finalize(&self, state: AggregateState) -> DataValue

Finalize and return the result

fn requires_numeric(&self) -> bool

Check if this function requires numeric input

Auto Trait Implementations§

impl Freeze for CountFunction

impl RefUnwindSafe for CountFunction

impl Send for CountFunction

impl Sync for CountFunction

impl Unpin for CountFunction

impl UnwindSafe for CountFunction

Blanket Implementations§

impl<T> Any for T
where T: 'static + ?Sized,

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impl<T> Borrow<T> for T
where T: ?Sized,

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Mutably borrows from an owned value. Read more

impl<T> From<T> for T

fn from(t: T) -> T

Returns the argument unchanged.

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Instruments this type with the provided Span, returning an Instrumented wrapper. Read more

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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

type Error = <U as TryFrom<T>>::Error

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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

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impl<V, T> VZip<V> for T
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