chenjunjiedada commented on a change in pull request #2841: URL: https://github.com/apache/iceberg/pull/2841#discussion_r709284031
########## File path: core/src/main/java/org/apache/iceberg/actions/RewriteDeleteStrategy.java ########## @@ -0,0 +1,76 @@ +/* + * 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.actions; + +import java.util.Map; +import java.util.Set; +import org.apache.iceberg.DeleteFile; +import org.apache.iceberg.FileScanTask; +import org.apache.iceberg.Table; + +public interface RewriteDeleteStrategy { + + /** + * Returns the name of this rewrite deletes strategy + */ + String name(); + + /** + * Returns the table being modified by this rewrite strategy + */ + Table table(); + + /** + * Select the deletes to rewrite. + * + * @param dataFiles iterable of FileScanTasks for data files in a given partition + * @return iterable of original delete file to be replaced. + */ + Iterable<DeleteFile> selectDeletesToRewrite(Iterable<FileScanTask> dataFiles); + + /** + * Define how to rewrite the deletes. + * + * @param deleteFilesToRewrite a group of files to be rewritten together + * @return iterable of delete files used to replace the original delete files. + */ + Set<DeleteFile> rewriteDeletes(Set<DeleteFile> deleteFilesToRewrite); Review comment: Good question! Besides converting to position deletes we could split equality delete into small ones so that each file scan can carry small equality deletes as Jack mentioned before. But as you pointed out, I think it would be hard to handle the sequence number since the committed snapshot should be immutable. Can we do the trick? I'm not sure how much benefit that splitting can provide, but I believe small files bring worse problems. How about we make `rewriteDeletes` more specific? Like `removeEqDeletes` and `rewritePosDeletes`. -- 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]
