imply-cheddar commented on code in PR #13458: URL: https://github.com/apache/druid/pull/13458#discussion_r1040159988
########## processing/src/main/java/org/apache/druid/query/rowsandcols/GroupPartitioner.java: ########## @@ -0,0 +1,43 @@ +/* + * 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.druid.query.rowsandcols; + +import java.util.List; + +/** + * A semantic interface used to partition a data set based on a given set of dimensions. + */ +@SuppressWarnings("unused") +public interface GroupPartitioner +{ + /** + * Computes the groupings of the underlying rows based on the columns passed in for grouping. The grouping is + * returned as an int[], the length of the array will be equal to the number of rows of data and the values of + * the elements of the array will be the same when the rows are part of the same group and different when the + * rows are part of different groups. This is contrasted with the SortedGroupPartitioner in that, the + * groupings returned are not necessarily contiguous. There is also no sort-order implied by the `int` values + * assigned to each grouping. + * + * @param columns the columns to group with + * @return the groupings, rows with the same int value are in the same group. There is no sort-order implied by the + * int values. + */ + int[] computeGroupings(List<String> columns); Review Comment: Yeah... this interface is probably gonna die anyway, it's not actually used in this PR anyway. -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
