| /* |
| * 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; |
| |
| /** |
| * An isolation level in a table. |
| * <p> |
| * Two isolation levels are supported: serializable and snapshot isolation. Both of them provide |
| * a read consistent view of the table to all operations and allow readers to see only already |
| * committed data. While serializable is the strongest isolation level in databases, |
| * snapshot isolation is beneficial for environments with many concurrent writers. |
| * <p> |
| * The serializable isolation level guarantees that an ongoing UPDATE/DELETE/MERGE operation |
| * fails if a concurrent transaction commits a new file that might contain rows matching |
| * the condition used in UPDATE/DELETE/MERGE. For example, if there is an ongoing update |
| * on a subset of rows and a concurrent transaction adds a new file with records |
| * that potentially match the update condition, the update operation must fail under |
| * the serializable isolation but can still commit under the snapshot isolation. |
| */ |
| public enum IsolationLevel { |
| SERIALIZABLE, SNAPSHOT |
| } |
