johnclara commented on a change in pull request #351: Provide an API to modify records within files URL: https://github.com/apache/incubator-iceberg/pull/351#discussion_r311741878
########## File path: core/src/main/java/org/apache/iceberg/DefaultModifyFiles.java ########## @@ -0,0 +1,114 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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 org.apache.iceberg; + +import com.google.common.base.Preconditions; +import com.google.common.collect.Iterables; +import java.util.ArrayList; +import java.util.List; +import java.util.Set; +import org.apache.iceberg.exceptions.ValidationException; +import org.apache.iceberg.expressions.Evaluator; +import org.apache.iceberg.expressions.Expression; +import org.apache.iceberg.expressions.Projections; + +public class DefaultModifyFiles extends MergingSnapshotProducer<ModifyFiles> implements ModifyFiles { + + private Long baseSnapshotId; + private Expression rowFilter; + + DefaultModifyFiles(TableOperations ops, Long baseSnapshotId) { + super(ops); + this.baseSnapshotId = baseSnapshotId; + // modify files must fail if any of the deleted paths is missing and cannot be deleted + failMissingDeletePaths(); + } + + @Override + protected ModifyFiles self() { + return this; + } + + @Override + protected String operation() { + return DataOperations.MODIFY; + } + + @Override + public ModifyFiles modifyFiles(Set<DataFile> filesToDelete, Set<DataFile> filesToAdd) { + Preconditions.checkArgument(filesToDelete != null, "Files to delete cannot be null"); + Preconditions.checkArgument(filesToAdd != null, "Files to add cannot be null"); + + for (DataFile toDelete : filesToDelete) { + delete(toDelete.path()); + } + + for (DataFile toAdd : filesToAdd) { + add(toAdd); + } + + return this; + } + + @Override + public ModifyFiles failOnNewFiles(Expression newRowFilter) { + Preconditions.checkArgument(newRowFilter != null, "Row filter cannot be null"); + this.rowFilter = newRowFilter; + return this; + } + + @Override + public List<ManifestFile> apply(TableMetadata base) { + if (rowFilter != null) { + PartitionSpec spec = writeSpec(); + Expression inclusiveExpr = Projections.inclusive(spec).project(rowFilter); + Evaluator inclusive = new Evaluator(spec.partitionType(), inclusiveExpr); + + List<DataFile> newFiles = collectNewFiles(base); + for (DataFile newFile : newFiles) { + // we do partition-level conflict resolution right now + // we can enhance it by leveraging column stats and MetricsEvaluator + ValidationException.check(!inclusive.eval(newFile.partition()), + "Modify operation detected a new file %s that might match %s", newFile.path(), rowFilter); + } + } + + return super.apply(base); + } + + private List<DataFile> collectNewFiles(TableMetadata meta) { + List<DataFile> newFiles = new ArrayList<>(); + + Long currentSnapshotId = meta.currentSnapshot() == null ? null : meta.currentSnapshot().snapshotId(); + while (currentSnapshotId != null && !currentSnapshotId.equals(baseSnapshotId)) { + Snapshot currentSnapshot = meta.snapshot(currentSnapshotId); + + if (currentSnapshot == null) { + throw new ValidationException( + "Modify operation cannot find snapshot %d. Was it expired?", currentSnapshotId); + } + + Iterables.addAll(newFiles, currentSnapshot.addedFiles()); Review comment: Should we also collect removed files? Is that feasible? If you are doing an update on a certain condition my understanding of the current flow is: 1. find a row matching that condition 2. create a new file with a corresponding row for that condition 3. a separate process deletes that file 4. you recreate that row in a new file when maybe you don't want that row recreated ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
