Trait GroupByColumns 

pub trait GroupByColumns {
    // Required method
    fn column_names(&self) -> Vec<String>;
}

GroupByColumns trait - 用于 group_by 方法的返回类型

Required Methods

fn column_names(&self) -> Vec<String>

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl<T1, T2, T3> GroupByColumns for (TypedColumn<T1>, TypedColumn<T2>, TypedColumn<T3>)

fn column_names(&self) -> Vec<String>

impl<T1, T2> GroupByColumns for (TypedColumn<T1>, TypedColumn<T2>)

fn column_names(&self) -> Vec<String>

Implementors

impl<T> GroupByColumns for TypedColumn<T>