org.apache.beam.sdk.extensions.sql.impl.rel

Class BeamUnionRel

java.lang.Object

Union

org.apache.beam.sdk.extensions.sql.impl.rel.BeamUnionRel

All Implemented Interfaces:

BeamRelNode

public class BeamUnionRel
extends Union
implements BeamRelNode

BeamRelNode to replace a Union.

BeamUnionRel needs the input of it have the same WindowFn. From the SQL perspective, two cases are supported:

1) Do not use grouped window function:

   select * from person UNION select * from person
 

2) Use the same grouped window function, with the same param:

   select id, count(*) from person
   group by id, TUMBLE(order_time, INTERVAL '1' HOUR)
   UNION
   select * from person
   group by id, TUMBLE(order_time, INTERVAL '1' HOUR)
 

Inputs with different group functions are NOT supported:

   select id, count(*) from person
   group by id, TUMBLE(order_time, INTERVAL '1' HOUR)
   UNION
   select * from person
   group by id, TUMBLE(order_time, INTERVAL '2' HOUR)
 

Constructor Summary

Constructors

Constructor and Description
BeamUnionRel(RelOptCluster cluster, RelTraitSet traits, java.util.List<RelNode> inputs, boolean all)

Method Summary

Modifier and Type	Method and Description
SetOp	copy(RelTraitSet traitSet, java.util.List<RelNode> inputs, boolean all)
PTransform<PCollectionTuple,PCollection<Row>>	toPTransform() A BeamRelNode is a recursive structure, the BeamQueryPlanner visits it with a DFS(Depth-First-Search) algorithm.

Methods inherited from class java.lang.Object

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

Constructor Detail

BeamUnionRel

public BeamUnionRel(RelOptCluster cluster,
                    RelTraitSet traits,
                    java.util.List<RelNode> inputs,
                    boolean all)

Method Detail

copy

public SetOp copy(RelTraitSet traitSet,
                  java.util.List<RelNode> inputs,
                  boolean all)

toPTransform

public PTransform<PCollectionTuple,PCollection<Row>> toPTransform()

Description copied from interface: BeamRelNode

A BeamRelNode is a recursive structure, the BeamQueryPlanner visits it with a DFS(Depth-First-Search) algorithm.

Specified by:

toPTransform in interface BeamRelNode