Trait datafusion::exec::SimpleRelation

pub trait SimpleRelation {
    fn scan<'a>(
        &'a self, 
        ctx: &'a ExecutionContext
    ) -> Box<Iterator<Item = Result<Row, ExecutionError>> + 'a>;
    fn schema<'a>(&'a self) -> &'a Schema;
}

trait for all relations (a relation is essentially just an iterator over rows with a known schema)

Required Methods

fn scan<'a>(
    &'a self,
    ctx: &'a ExecutionContext
) -> Box<Iterator<Item = Result<Row, ExecutionError>> + 'a>

scan all records in this relation

fn schema<'a>(&'a self) -> &'a Schema

get the schema for this relation

Implementors

• impl SimpleRelation for CsvRelation
• impl SimpleRelation for FilterRelation
• impl SimpleRelation for SortRelation
• impl SimpleRelation for ProjectRelation
• impl SimpleRelation for LimitRelation