org.apache.hadoop.hive.ql.optimizer.calcite.rules.views

Class MaterializedViewRewritingRelVisitor

java.lang.Object

org.apache.calcite.rel.RelVisitor

org.apache.hadoop.hive.ql.optimizer.calcite.rules.views.MaterializedViewRewritingRelVisitor

public class MaterializedViewRewritingRelVisitor
extends org.apache.calcite.rel.RelVisitor

This class is a helper to check whether a materialized view rebuild can be transformed from INSERT OVERWRITE to INSERT INTO. We are verifying that: 1) the rewriting is rooted by legal operators (Filter and Project) before reaching a Union operator, 2) the left branch uses the MV that we are trying to rebuild and legal operators (Filter and Project), and 3) the right branch only uses legal operators (i.e., Filter, Project, Join, and TableScan)

Constructor Summary

Constructors

Constructor and Description
MaterializedViewRewritingRelVisitor()

Method Summary

Modifier and Type	Method and Description
org.apache.calcite.rel.RelNode	go(org.apache.calcite.rel.RelNode p) Starts an iteration.
boolean	isContainsAggregate()
boolean	isRewritingAllowed()
void	visit(org.apache.calcite.rel.RelNode node, int ordinal, org.apache.calcite.rel.RelNode parent)

Methods inherited from class org.apache.calcite.rel.RelVisitor

replaceRoot

Methods inherited from class java.lang.Object

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

Constructor Detail

MaterializedViewRewritingRelVisitor

public MaterializedViewRewritingRelVisitor()

Method Detail

visit

public void visit(org.apache.calcite.rel.RelNode node,
                  int ordinal,
                  org.apache.calcite.rel.RelNode parent)

Overrides:

visit in class org.apache.calcite.rel.RelVisitor

go

public org.apache.calcite.rel.RelNode go(org.apache.calcite.rel.RelNode p)

Starts an iteration.

Overrides:

go in class org.apache.calcite.rel.RelVisitor

isContainsAggregate

public boolean isContainsAggregate()

isRewritingAllowed

public boolean isRewritingAllowed()