tarun11Mavani commented on code in PR #18643: URL: https://github.com/apache/pinot/pull/18643#discussion_r3503446183
########## pinot-segment-local/src/main/java/org/apache/pinot/segment/local/segment/index/openstruct/ImmutableOpenStructDataSource.java: ########## @@ -0,0 +1,265 @@ +/** + * 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.pinot.segment.local.segment.index.openstruct; + +import java.io.IOException; +import java.util.HashMap; +import java.util.Map; +import javax.annotation.Nullable; +import org.apache.pinot.segment.local.segment.index.datasource.BaseDataSource; +import org.apache.pinot.segment.local.segment.index.datasource.ImmutableDataSource; +import org.apache.pinot.segment.spi.Constants; +import org.apache.pinot.segment.spi.datasource.DataSource; +import org.apache.pinot.segment.spi.datasource.DataSourceMetadata; +import org.apache.pinot.segment.spi.datasource.OpenStructDataSource; +import org.apache.pinot.segment.spi.index.column.ColumnIndexContainer; +import org.apache.pinot.segment.spi.index.reader.Dictionary; +import org.apache.pinot.segment.spi.index.reader.ForwardIndexReader; +import org.apache.pinot.segment.spi.index.reader.ForwardIndexReaderContext; +import org.apache.pinot.segment.spi.index.reader.NullValueVectorReader; +import org.apache.pinot.segment.spi.partition.PartitionFunction; +import org.apache.pinot.spi.data.ComplexFieldSpec; +import org.apache.pinot.spi.data.FieldSpec; +import org.apache.pinot.spi.data.FieldSpec.DataType; +import org.apache.pinot.spi.utils.JsonUtils; + + + +/// Per-key {@link DataSource} accessor for sealed (immutable) segments with an OPEN_STRUCT column. +/// +/// Always columnar — there is no blob branch. Every key that was dense enough during segment +/// creation gets its own materialized {@link DataSource} (forward index + optional inverted index / +/// dictionary). Keys that did not meet the density threshold are stored in an optional sparse +/// column; the sparse {@link DataSource} is returned for any unmaterialized key lookup. +/// +/// Use [#isMaterialized(String)] and [#isFullyMaterialized()] together to choose +/// the query execution path: +/// - Materialized key → fast path via per-key DataSource (inverted/dictionary index available). +/// - Not materialized + not fully materialized → fall back to the sparse DataSource. +/// - Not materialized + fully materialized → key is definitively absent; short-circuit. +/// +/// Thread-safety: immutable after construction; safe for concurrent reads. +public class ImmutableOpenStructDataSource extends BaseDataSource implements OpenStructDataSource { + private final ComplexFieldSpec _fieldSpec; + private final Map<String, DataSource> _perKeyDataSources; + @Nullable + private final DataSource _sparseDataSource; + + public ImmutableOpenStructDataSource(ComplexFieldSpec fieldSpec, Map<String, DataSource> perKeyDataSources, + @Nullable DataSource sparseDataSource, DataSourceMetadata dataSourceMetadata, + ColumnIndexContainer indexContainer) { + super(dataSourceMetadata, indexContainer); + _fieldSpec = fieldSpec; + _perKeyDataSources = perKeyDataSources; + _sparseDataSource = sparseDataSource; + } + + /// Convenience constructor for segment-load time. Synthesizes a minimal {@link DataSourceMetadata} + /// for the parent OPEN_STRUCT column (which has no on-disk presence of its own) and uses an empty + /// {@link ColumnIndexContainer} — all real readers live on the per-key data sources. + public ImmutableOpenStructDataSource(ComplexFieldSpec fieldSpec, Map<String, DataSource> perKeyDataSources, + @Nullable DataSource sparseDataSource, int numDocs) { + this(fieldSpec, perKeyDataSources, sparseDataSource, + new ImmutableOpenStructDataSourceMetadata(fieldSpec, numDocs), + new ColumnIndexContainer.FromMap.Builder().build()); + } + Review Comment: The empty container is safe because no query operator calls `getForwardIndex()` on the parent OPEN_STRUCT DataSource — they go through `getDataSource(key)` to access per-key child DataSources. But I agree it's not clean. This ties into comment 4 — if we introduce a shared `CompositeDataSource` base for MAP and OPEN_STRUCT, it could drop the `ColumnIndexContainer` requirement entirely for composite parents. I'd prefer to do that as a follow-up rather than diverge OPEN_STRUCT from MAP's pattern in this PR. -- 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]
