io.trino.sql.planner.iterative.rule.PushOffsetThroughProject Maven / Gradle / Ivy
/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.trino.sql.planner.iterative.rule;
import io.trino.matching.Capture;
import io.trino.matching.Captures;
import io.trino.matching.Pattern;
import io.trino.sql.planner.iterative.Rule;
import io.trino.sql.planner.plan.OffsetNode;
import io.trino.sql.planner.plan.ProjectNode;
import static io.trino.matching.Capture.newCapture;
import static io.trino.sql.planner.iterative.rule.Util.transpose;
import static io.trino.sql.planner.plan.Patterns.offset;
import static io.trino.sql.planner.plan.Patterns.project;
import static io.trino.sql.planner.plan.Patterns.source;
/**
* Transforms:
*
* - Offset
* - Project (non identity)
*
* Into:
*
* - Project (non identity)
* - Offset
*
*/
public class PushOffsetThroughProject
implements Rule
{
private static final Capture CHILD = newCapture();
private static final Pattern PATTERN = offset()
.with(source().matching(
project()
// do not push offset through identity projection which could be there for column pruning purposes
.matching(projectNode -> !projectNode.isIdentity())
.capturedAs(CHILD)));
@Override
public Pattern getPattern()
{
return PATTERN;
}
@Override
public Result apply(OffsetNode parent, Captures captures, Context context)
{
return Result.ofPlanNode(transpose(parent, captures.get(CHILD)));
}
}