danny0405 commented on a change in pull request #4880: URL: https://github.com/apache/hudi/pull/4880#discussion_r838225305
########## File path: hudi-common/src/main/java/org/apache/hudi/common/table/log/HoodieMergedLogRecordScanner.java ########## @@ -153,9 +154,29 @@ protected void processNextRecord(HoodieRecord<? extends HoodieRecordPayload> hoo } @Override - protected void processNextDeletedKey(HoodieKey hoodieKey) { - records.put(hoodieKey.getRecordKey(), SpillableMapUtils.generateEmptyPayload(hoodieKey.getRecordKey(), - hoodieKey.getPartitionPath(), getPayloadClassFQN())); + protected void processNextDeletedRecord(DeleteRecord deleteRecord) { + String key = deleteRecord.getRecordKey(); + if (records.containsKey(key)) { + // Merge and store the merged record. The ordering val is taken to decide whether the same key record + // should be deleted or be kept. The old record is kept only if the DELETE record has smaller ordering val. + // For same ordering values, uses the natural order(arrival time semantics). + + HoodieRecord<? extends HoodieRecordPayload> oldRecord = records.get(key); + Comparable curOrderingVal = oldRecord.getData().getCombineValue(); + Comparable deleteOrderingVal = deleteRecord.getOrderingVal(); + // Checks the ordering value does not equal to 0 + // because we use 0 as the default value which means natural order + boolean choosePrev = !deleteOrderingVal.equals(0) + && curOrderingVal.getClass() == deleteOrderingVal.getClass() + && curOrderingVal.compareTo(deleteOrderingVal) > 0; Review comment: The concrete proposal original was to solve the data lost when there are: `DELETE`, `INSERT` events in one transaction/commit of hoodie table, if the events have correct event time field. What the patch can not solve is: when the events have same event time field(processing sequence), the data would still be lost. -- 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: commits-unsubscr...@hudi.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org