Trait datafusion::dataframe::DataFrame [−] [src]

pub trait DataFrame {
    fn repartition(&self, n: u32) -> Result<Box<DataFrame>, DataFrameError>;
    fn select(&self, expr: Vec<Expr>) -> Result<Box<DataFrame>, DataFrameError>;
    fn filter(&self, expr: Expr) -> Result<Box<DataFrame>, DataFrameError>;
    fn sort(&self, expr: Vec<Expr>) -> Result<Box<DataFrame>, DataFrameError>;
    fn write(&self, filename: &str) -> Result<(), DataFrameError>;
    fn col(&self, column_name: &str) -> Result<Expr, DataFrameError>;
    fn schema(&self) -> Schema;
}

DataFrame is an abstraction of a distributed query plan

Required Methods

`fn repartition(&self, n: u32) -> Result<Box<DataFrame>, DataFrameError>`

Change the number of partitions

`fn select(&self, expr: Vec<Expr>) -> Result<Box<DataFrame>, DataFrameError>`

Projection

`fn filter(&self, expr: Expr) -> Result<Box<DataFrame>, DataFrameError>`

Selection

`fn sort(&self, expr: Vec<Expr>) -> Result<Box<DataFrame>, DataFrameError>`

Sorting

`fn write(&self, filename: &str) -> Result<(), DataFrameError>`

Write to CSV ... will support other formats in the future

`fn col(&self, column_name: &str) -> Result<Expr, DataFrameError>`

Return an expression representing the specified column

`fn schema(&self) -> Schema`

Implementors

impl DataFrame for DF