Trait VarProvider 

pub trait VarProvider: Debug {
    // Required methods
    fn get_value(
        &self,
        var_names: Vec<String>,
    ) -> Result<ScalarValue, DataFusionError>;
    fn get_type(&self, var_names: &[String]) -> Option<DataType>;
}

A var provider for @variable and @@variable runtime values.

Required Methods

fn get_value( &self, var_names: Vec<String>, ) -> Result<ScalarValue, DataFusionError>

Get variable value

fn get_type(&self, var_names: &[String]) -> Option<DataType>

Return the type of the given variable

Dyn Compatibility

This trait is dyn compatible.

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

Implementations on Foreign Types

impl VarProvider for SystemVar

fn get_value( &self, var_names: Vec<String>, ) -> Result<ScalarValue, DataFusionError>

get system variable value

fn get_type(&self, _: &[String]) -> Option<DataType>

impl VarProvider for UserDefinedVar

fn get_value( &self, var_names: Vec<String>, ) -> Result<ScalarValue, DataFusionError>

Get user defined variable value

fn get_type(&self, var_names: &[String]) -> Option<DataType>

Implementors