sanpwc commented on a change in pull request #91: URL: https://github.com/apache/ignite-3/pull/91#discussion_r632561029
########## File path: modules/schema/src/main/java/org/apache/ignite/internal/schema/registry/SchemaRegistryImpl.java ########## @@ -0,0 +1,179 @@ +/* + * 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.ignite.internal.schema.registry; + +import java.util.List; +import java.util.Objects; +import java.util.concurrent.ConcurrentSkipListMap; +import org.apache.ignite.internal.schema.SchemaDescriptor; +import org.apache.ignite.internal.schema.SchemaRegistry; +import org.jetbrains.annotations.Nullable; + +/** + * Holds schema descriptors for actual schema versions. + * <p> + * Schemas MUST be registered in a version ascending order incrementing by {@code 1} with NO gaps, + * otherwise an exception will be thrown. The version numbering starts from the {@code 1}. + * <p> + * After some table maintenance process some first versions may become outdated and can be safely cleaned up + * if the process guarantees the table no longer has a data of these versions. + * + * @implSpec The changes in between two arbitrary actual versions MUST NOT be lost. + * Thus, schema versions can only be removed from the beginning. + * @implSpec Initial schema history MAY be registered without the first outdate versions Review comment: outdate->outdated -- This is an automated message from the Apache Git Service.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. For queries about this service, please contact Infrastructure at: [email protected]
