pub fn reduce(
        self,
        group_key: Vec<usize>,
        aggregates: Vec<AggregateExpr>,
        expected_group_size: Option<usize>,
    ) -> Self {
        MirRelationExpr::Reduce {
            input: Box::new(self),
            group_key: group_key.into_iter().map(MirScalarExpr::Column).collect(),
            aggregates,
            monotonic: false,
            expected_group_size,
        }
    }
/// Perform a key-wise reduction / aggregation.
///
/// The `group_key` argument indicates columns in the input collection that should
/// be grouped, and `aggregates` lists aggregation functions each of which produces
/// one output column in addition to the keys.
Perform a key-wise reduction / aggregation.
The `group_key` argument indicates columns in the input collection that should
be grouped, and `aggregates` lists aggregation functions each of which produces
one output column in addition to the keys.
Perform a key - wise reduction / aggregation . The ` group_key ` argument indicates columns in the input collection that should be grouped and ` aggregates ` lists aggregation functions each of which produces one output column in addition to the keys .
pub fn reduce(
        self,
        group_key: Vec<usize>,
        aggregates: Vec<AggregateExpr>,
        expected_group_size: Option<usize>,
    ) -> Self {
        MirRelationExpr::Reduce {
            input: Box::new(self),
            group_key: group_key.into_iter().map(MirScalarExpr::Column).collect(),
            aggregates,
            monotonic: false,
            expected_group_size,
        }
    }
pub fn reduce ( self , group_key : Vec < usize > , aggregates : Vec < AggregateExpr > , expected_group_size : Option < usize > , ) -> Self { MirRelationExpr :: Reduce { input : Box :: new ( self ) , group_key : group_key . into_iter ( ) . map ( MirScalarExpr :: Column ) . collect ( ) , aggregates , monotonic : false , expected_group_size , } }
Perform a key-wise reduction / aggregation.
Perform a key - wise reduction / aggregation .
self
group_key
Vec<usize>
aggregates
Vec<AggregateExpr>
expected_group_size
Option<usize>
self
group_key
Vec<usize>
aggregates
Vec<AggregateExpr>
expected_group_size
Option<usize>