julianhyde commented on code in PR #4561: URL: https://github.com/apache/calcite/pull/4561#discussion_r2389606045
########## core/src/main/java/org/apache/calcite/rel/metadata/FunctionalDependencies.java: ########## @@ -0,0 +1,305 @@ +/* + * 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.calcite.rel.metadata; + +import com.google.common.collect.ImmutableSet; + +import java.util.ArrayDeque; +import java.util.Comparator; +import java.util.HashMap; +import java.util.HashSet; +import java.util.Map; +import java.util.PriorityQueue; +import java.util.Queue; +import java.util.Set; +import java.util.stream.Collectors; + +import static java.util.Objects.requireNonNull; + +/** + * Models a set of functional dependencies and provides methods for closure computation, + * candidate key search, and related reasoning. + */ +public class FunctionalDependencies { Review Comment: This class at first looks like a nice low-level library for functional dependencies. Its plural name implies that it is a utility class but it is not a utility class: it has data fields and is instantiable. You use terms like 'dependent' and 'determinant' without defining them. I think this can be fixed. You need to find better names than "FunctionalDependencies" and "FunctionalDependency", and you need to write a reasonable amount of javadoc with some examples in it. -- 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]
