anoopj commented on code in PR #17541: URL: https://github.com/apache/iceberg/pull/17541#discussion_r3732342039
########## core/src/main/java/org/apache/iceberg/ManifestExpander.java: ########## @@ -0,0 +1,325 @@ +/* + * 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.github.benmanes.caffeine.cache.Caffeine; +import com.github.benmanes.caffeine.cache.LoadingCache; +import java.io.IOException; +import java.io.UncheckedIOException; +import java.util.List; +import java.util.Map; +import java.util.concurrent.ExecutorService; +import org.apache.iceberg.expressions.Expression; +import org.apache.iceberg.expressions.Expressions; +import org.apache.iceberg.expressions.ResidualEvaluator; +import org.apache.iceberg.io.CloseableGroup; +import org.apache.iceberg.io.CloseableIterable; +import org.apache.iceberg.io.CloseableIterator; +import org.apache.iceberg.io.FileIO; +import org.apache.iceberg.io.InputFile; +import org.apache.iceberg.metrics.ScanMetrics; +import org.apache.iceberg.metrics.ScanMetricsUtil; +import org.apache.iceberg.relocated.com.google.common.base.Preconditions; +import org.apache.iceberg.relocated.com.google.common.collect.ImmutableMap; +import org.apache.iceberg.relocated.com.google.common.collect.Lists; +import org.apache.iceberg.util.ParallelIterable; + +/** + * Planner that expands the adaptive metadata tree into {@link FileScanTask}s. + * + * <p>Emits a task for each live {@code DATA} entry and expands {@code DATA_MANIFEST} entries into + * their leaf manifests. A data entry's colocated deletion vector is attached to its task as a + * {@link DeleteFile}. + * + * <p>Emitted tasks do not yet carry inherited tracking: leaf and root {@code DATA} entries are not + * assigned the data/file sequence numbers, snapshot id, and first-row-id they inherit from their + * parent, so {@code data_sequence_number}, {@code file_sequence_number}, and row-lineage columns + * ({@code _row_id}, {@code _last_updated_sequence_number}) read null for added files. Inheritance + * must be applied before this planner is wired into a scan or the delete-manifest matching path, + * since delete scoping compares a data file's sequence number against the delete's. + */ +class ManifestExpander { Review Comment: This is a great question. The intent here is that this is the V4 analog of the existing package-private `ManifestGroup` helper, and not a new node in the scan hierarchy. Today `DataTableScan.doPlanFiles()` builds a `ManifestGroup` and calls `.planFiles()` to turn manifests into FileScanTasks. ManifestExpander plays the same role for the V4 metadata tree: doPlanFiles() (or a doPlanFilesV4() branch, dispatched on format version) will build one and call planFiles(), exactly mirroring the current flow. So it lives below the scan hierarchy and is consumed by rather than being implemented within `DataTableScan/BaseTableScan/SnapshotScan` themselves. You can see how this could be used in the prototype PR [here](https://github.com/apache/iceberg/pull/16150/changes#diff-68f831bb319578a644bd1024f51d85a09284bb34ebc5d9b7608362b24caf441a). -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
