clohfink commented on code in PR #3857: URL: https://github.com/apache/cassandra/pull/3857#discussion_r1939750663
########## src/java/org/apache/cassandra/db/virtual/PrimaryIdTable.java: ########## @@ -0,0 +1,356 @@ +/* + * 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.cassandra.db.virtual; + +import java.io.IOException; +import java.math.BigInteger; +import java.nio.ByteBuffer; +import java.util.List; +import java.util.concurrent.CopyOnWriteArrayList; +import java.util.function.Consumer; + +import com.google.common.annotations.VisibleForTesting; +import com.google.common.collect.Lists; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import org.apache.cassandra.cql3.Operator; +import org.apache.cassandra.db.Clustering; +import org.apache.cassandra.db.ColumnFamilyStore; +import org.apache.cassandra.db.DataRange; +import org.apache.cassandra.db.DecoratedKey; +import org.apache.cassandra.db.DeletionTime; +import org.apache.cassandra.db.PartitionPosition; +import org.apache.cassandra.db.Slice; +import org.apache.cassandra.db.Slices; +import org.apache.cassandra.db.context.CounterContext; +import org.apache.cassandra.db.filter.ClusteringIndexFilter; +import org.apache.cassandra.db.filter.ColumnFilter; +import org.apache.cassandra.db.filter.RowFilter; +import org.apache.cassandra.db.marshal.CompositeType; +import org.apache.cassandra.db.marshal.CounterColumnType; +import org.apache.cassandra.db.marshal.IntegerType; +import org.apache.cassandra.db.marshal.UTF8Type; +import org.apache.cassandra.db.partitions.PartitionUpdate; +import org.apache.cassandra.db.partitions.SingletonUnfilteredPartitionIterator; +import org.apache.cassandra.db.partitions.UnfilteredPartitionIterator; +import org.apache.cassandra.db.rows.AbstractUnfilteredRowIterator; +import org.apache.cassandra.db.rows.BTreeRow; +import org.apache.cassandra.db.rows.BufferCell; +import org.apache.cassandra.db.rows.Cell; +import org.apache.cassandra.db.rows.EncodingStats; +import org.apache.cassandra.db.rows.Row; +import org.apache.cassandra.db.rows.Rows; +import org.apache.cassandra.db.rows.Unfiltered; +import org.apache.cassandra.db.rows.UnfilteredRowIterator; +import org.apache.cassandra.db.rows.UnfilteredRowIterators; +import org.apache.cassandra.dht.AbstractBounds; +import org.apache.cassandra.dht.Bounds; +import org.apache.cassandra.dht.LocalPartitioner; +import org.apache.cassandra.dht.Range; +import org.apache.cassandra.dht.Token; +import org.apache.cassandra.exceptions.InvalidRequestException; +import org.apache.cassandra.io.sstable.KeyReader; +import org.apache.cassandra.io.sstable.format.SSTableReader; +import org.apache.cassandra.schema.ColumnMetadata; +import org.apache.cassandra.schema.KeyspaceMetadata; +import org.apache.cassandra.schema.Schema; +import org.apache.cassandra.schema.TableMetadata; + +import static org.apache.cassandra.cql3.statements.RequestValidations.invalidRequest; + +/** + * A virtual table for querying primary IDs of SSTables in a specific keyspace. + * + * <p>This table is implemented as a virtual table in Cassandra, meaning it does not + * store data persistently on disk but instead derives its data from live metadata. + * + * <p>The CQL equivalent of this virtual table is: + * <pre> + * CREATE TABLE system_views.primary_ids ( + * keyspace_name TEXT, + * table_name TEXT, + * token_value INT, + * key TEXT, + * size_estimate COUNTER, + * sstables COUNTER, + * PRIMARY KEY ((keyspace_name, table_name), token_value, key) + * ); + * </pre> + * + * <p>Note: + * <ul> + * <li>The `size_estimate` and `sstables` columns represent aggregate information about SSTable sizes and counts.</li> + * <li>Range queries across multiple tables and updates are not supported as this is a read-only table.</li> + * </ul> + */ +public class PrimaryIdTable implements VirtualTable Review Comment: no. the abstract virtual table builds the entire result within a Dataset that it then filters/moves around. This returns only the parts that are requested so we don't OOM -- 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]
