org.apache.flink.api.table.plan

Class ExpandAggregations

java.lang.Object

org.apache.flink.api.table.plan.ExpandAggregations

public class ExpandAggregations
extends Object

This is used to expand a Select that contains aggregations. If it is called on a Select without aggregations it is simply returned.

This select:

   in.select('key, 'value.avg)
 

is transformed to this expansion:

   in
     .select('key, 'value, Literal(1) as 'intermediate.1)
     .aggregate('value.sum, 'intermediate.1.sum)
     .select('key, 'value / 'intermediate.1)
 

If the input of the Select is a GroupBy this is preserved before the aggregation.

Constructor Summary

Constructors

Constructor and Description
ExpandAggregations()

Method Summary

Modifier and Type	Method and Description
static PlanNode	apply(Select select)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ExpandAggregations

public ExpandAggregations()

Method Detail

apply

public static PlanNode apply(Select select)