Trait GroupedDataBackend 

pub trait GroupedDataBackend: Send + Sync {
    // Required methods
    fn agg(
        &self,
        exprs: &[ExprIr],
    ) -> Result<Box<dyn DataFrameBackend>, EngineError>;
    fn count(&self) -> Result<Box<dyn DataFrameBackend>, EngineError>;
    fn sum(
        &self,
        column: &str,
    ) -> Result<Box<dyn DataFrameBackend>, EngineError>;
    fn min(
        &self,
        column: &str,
    ) -> Result<Box<dyn DataFrameBackend>, EngineError>;
    fn max(
        &self,
        column: &str,
    ) -> Result<Box<dyn DataFrameBackend>, EngineError>;
    fn mean(
        &self,
        column: &str,
    ) -> Result<Box<dyn DataFrameBackend>, EngineError>;
    fn avg(
        &self,
        columns: &[&str],
    ) -> Result<Box<dyn DataFrameBackend>, EngineError>;
}

Backend for GroupedData (result of group_by).

Required Methods

fn agg( &self, exprs: &[ExprIr], ) -> Result<Box<dyn DataFrameBackend>, EngineError>

fn count(&self) -> Result<Box<dyn DataFrameBackend>, EngineError>

fn sum(&self, column: &str) -> Result<Box<dyn DataFrameBackend>, EngineError>

fn min(&self, column: &str) -> Result<Box<dyn DataFrameBackend>, EngineError>

fn max(&self, column: &str) -> Result<Box<dyn DataFrameBackend>, EngineError>

fn mean(&self, column: &str) -> Result<Box<dyn DataFrameBackend>, EngineError>

fn avg( &self, columns: &[&str], ) -> Result<Box<dyn DataFrameBackend>, EngineError>

Implementors