ajian2002 commented on code in PR #121: URL: https://github.com/apache/flink-table-store/pull/121#discussion_r872990828
########## flink-table-store-core/src/main/java/org/apache/flink/table/store/file/mergetree/compact/AggregationMergeFunction.java: ########## @@ -0,0 +1,104 @@ +/* + * 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.flink.table.store.file.mergetree.compact; + +import org.apache.flink.table.data.GenericRowData; +import org.apache.flink.table.data.RowData; + +import javax.annotation.Nullable; + +/** + * A {@link MergeFunction} where key is primary key (unique) and value is the partial record, update + * non-null fields on merge. + */ +public class AggregationMergeFunction implements MergeFunction { + + private static final long serialVersionUID = 1L; + + private final RowData.FieldGetter[] getters; + + private transient GenericRowData row; + + public AggregationMergeFunction(RowData.FieldGetter[] getters) { + this.getters = getters; + } + + @Override + public void reset() { + this.row = new GenericRowData(getters.length); + } + + @Override + public void add(RowData value) { + for (int i = 0; i < getters.length; i++) + { + Object currentField = getters[i].getFieldOrNull(value); + Object oldValue = row.getField(i); + Object result = sum(oldValue, currentField); + if (result != null) + { + row.setField(i, result); + } + } + } + + private Object sum(Object oldValue, Object currentField) { + if (currentField == null) + { + return null; + } + if (oldValue == null) + { + return currentField; + } + if (oldValue instanceof Integer && currentField instanceof Integer) + { + return Integer.sum((Integer) oldValue, (Integer) currentField); + } + else if (oldValue instanceof Long && currentField instanceof Long) + { + return Long.sum((Long) oldValue, (Long) currentField); + } Review Comment: should it be used org.apache.flink.api.java.aggregation.AggregationFunction to handle aggregation? This is a convenient way to deal with different field types, but it also brings some problems. It is difficult for me to deal with delete/update RowData#getRowKind. How to solve it? 1. Modify the original interface org.apache.flink.api.java.aggregation.AggregationFunction to add delete and update functions 2. Implement the Aggregator class by yourself, manually switch the class of different fields and implement it? Is there any other solution For the type processing of object/class, I guess flink/flink-table-store already has useful tool classes to reduce development workload (such as org.apache.flink.api.java.aggregation.AggregationFunction, etc.), you can provide guide? -- 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]
