/**
* Converts a relational expression to a form where {@link org.eigenbase.rel.JoinRel}s are as
* close to leaves as possible.
*/
public static RelNode toLeafJoinForm(RelNode rel) {
final HepProgramBuilder programBuilder = new HepProgramBuilder();
programBuilder.addRuleInstance(PullUpProjectsAboveJoinRule.instanceRightProjectChild);
programBuilder.addRuleInstance(PullUpProjectsAboveJoinRule.instanceLeftProjectChild);
final HepPlanner planner = new HepPlanner(programBuilder.createProgram());
planner.setRoot(rel);
System.out.println(
RelOptUtil.dumpPlan("before", rel, false, SqlExplainLevel.DIGEST_ATTRIBUTES));
final RelNode rel2 = planner.findBestExp();
System.out.println(
RelOptUtil.dumpPlan("after", rel2, false, SqlExplainLevel.DIGEST_ATTRIBUTES));
return rel2;
}
/**
* Converts a relational expression to a form where {@link org.eigenbase.rel.JoinRel}s are as
* close to leaves as possible.
*/
public static RelNode toLeafJoinForm(RelNode rel) {
HepProgram program =
HepProgram.builder()
.addRuleInstance(PullUpProjectsAboveJoinRule.RIGHT_PROJECT)
.addRuleInstance(PullUpProjectsAboveJoinRule.LEFT_PROJECT)
.build();
final HepPlanner planner =
new HepPlanner(
program, //
rel.getCluster().getPlanner().getContext());
planner.setRoot(rel);
System.out.println(
RelOptUtil.dumpPlan("before", rel, false, SqlExplainLevel.DIGEST_ATTRIBUTES));
final RelNode rel2 = planner.findBestExp();
System.out.println(
RelOptUtil.dumpPlan("after", rel2, false, SqlExplainLevel.DIGEST_ATTRIBUTES));
return rel2;
}