| /* |
| * 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.index.transactions; |
| |
| /** |
| * Base interface for the handling of index updates. |
| * There are 3 types of transaction where indexes are updated to stay in sync with the base table, each represented by |
| * a subinterface: |
| * * {@code UpdateTransaction} |
| * Used on the regular write path and when indexing newly acquired SSTables from streaming or sideloading. This type |
| * of transaction may include both row inserts and updates to rows previously existing in the base Memtable. Instances |
| * are scoped to a single partition update and are obtained from the factory method |
| * {@code SecondaryIndexManager#newUpdateTransaction} |
| * |
| * * {@code CompactionTransaction} |
| * Used during compaction when stale entries which have been superceded are cleaned up from the index. As rows in a |
| * partition are merged during the compaction, index entries for any purged rows are cleaned from the index to |
| * compensate for the fact that they may not have been removed at write time if the data in the base table had been |
| * already flushed to disk (and so was processed as an insert, not an update by the UpdateTransaction). These |
| * transactions are currently scoped to a single row within a partition, but this could be improved to batch process |
| * multiple rows within a single partition. |
| * |
| * * @{code CleanupTransaction} |
| * During cleanup no merging is required, the only thing to do is to notify indexes of the partitions being removed, |
| * along with the rows within those partitions. Like with compaction, these transactions are currently scoped to a |
| * single row within a partition, but this could be improved with batching. |
| */ |
| public interface IndexTransaction |
| { |
| /** |
| * Used to differentiate between type of index transaction when obtaining |
| * a handler from Index implementations. |
| */ |
| public enum Type |
| { |
| UPDATE, COMPACTION, CLEANUP |
| } |
| |
| void start(); |
| void commit(); |
| } |