CountStarFunction

sql_cli::sql::aggregates::functions

Struct CountStarFunction

pub struct CountStarFunction;

Expand description

COUNT(*) - counts all rows including nulls

Trait Implementations§

impl AggregateFunction for CountStarFunction

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 CountStarFunction

impl RefUnwindSafe for CountStarFunction

impl Send for CountStarFunction

impl Sync for CountStarFunction

impl Unpin for CountStarFunction

impl UnwindSafe for CountStarFunction

Blanket Implementations§

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

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where U: TryFrom<T>,

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