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https://issues.apache.org/jira/browse/HIVE-22977?focusedWorklogId=837804&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-837804
]
ASF GitHub Bot logged work on HIVE-22977:
-----------------------------------------
Author: ASF GitHub Bot
Created on: 09/Jan/23 05:16
Start Date: 09/Jan/23 05:16
Worklog Time Spent: 10m
Work Description: SourabhBadhya commented on code in PR #3801:
URL: https://github.com/apache/hive/pull/3801#discussion_r1064290065
##########
ql/src/java/org/apache/hadoop/hive/ql/txn/compactor/OrcFileMerger.java:
##########
@@ -0,0 +1,114 @@
+/*
+ * 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.hadoop.hive.ql.txn.compactor;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hive.ql.exec.vector.VectorizedRowBatch;
+import org.apache.hadoop.hive.ql.io.orc.CompressionKind;
+import org.apache.hadoop.hive.ql.io.orc.OrcFile;
+import org.apache.hadoop.hive.ql.io.orc.Reader;
+import org.apache.hadoop.hive.ql.io.orc.RecordReader;
+import org.apache.hadoop.hive.ql.io.orc.Writer;
+import org.apache.hadoop.fs.Path;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.util.List;
+
+/**
+ * Class to support fast merging of ORC files.
+ */
+public class OrcFileMerger {
+
+ private final Configuration conf;
+ private static final Logger LOG =
LoggerFactory.getLogger(OrcFileMerger.class);
+
+ public OrcFileMerger(Configuration conf) {
+ this.conf = conf;
+ }
+
+ /**
+ * Merge orc files into a single file
+ * @param files list of orc file paths to be merged
+ * @param outPath the path of output orc file
+ * @throws IOException error happened during file operations
+ */
+ public void mergeFiles(List<Reader> readers, Path outPath) throws
IOException {
+ Writer writer = null;
+ try {
+ for (Reader reader : readers) {
+ if (writer == null) {
+ writer = setupWriter(reader, outPath);
+ }
+ VectorizedRowBatch batch = reader.getSchema().createRowBatchV2();
+ RecordReader rows = reader.rows();
+ while (rows.nextBatch(batch)) {
+ if (batch != null) {
+ writer.addRowBatch(batch);
+ }
+ }
+ rows.close();
+ }
+ } finally {
+ if (writer != null) {
+ writer.close();
+ }
+ }
Review Comment:
If we create a writer irrespective of number of readers in try with
resources block then a writer will always be created and this may create a
empty file (if readers are not present).
##########
ql/src/java/org/apache/hadoop/hive/ql/txn/compactor/OrcFileMerger.java:
##########
@@ -0,0 +1,114 @@
+/*
+ * 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.hadoop.hive.ql.txn.compactor;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hive.ql.exec.vector.VectorizedRowBatch;
+import org.apache.hadoop.hive.ql.io.orc.CompressionKind;
+import org.apache.hadoop.hive.ql.io.orc.OrcFile;
+import org.apache.hadoop.hive.ql.io.orc.Reader;
+import org.apache.hadoop.hive.ql.io.orc.RecordReader;
+import org.apache.hadoop.hive.ql.io.orc.Writer;
+import org.apache.hadoop.fs.Path;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.util.List;
+
+/**
+ * Class to support fast merging of ORC files.
+ */
+public class OrcFileMerger {
+
+ private final Configuration conf;
+ private static final Logger LOG =
LoggerFactory.getLogger(OrcFileMerger.class);
+
+ public OrcFileMerger(Configuration conf) {
+ this.conf = conf;
+ }
+
+ /**
+ * Merge orc files into a single file
+ * @param files list of orc file paths to be merged
+ * @param outPath the path of output orc file
+ * @throws IOException error happened during file operations
+ */
+ public void mergeFiles(List<Reader> readers, Path outPath) throws
IOException {
+ Writer writer = null;
+ try {
+ for (Reader reader : readers) {
+ if (writer == null) {
+ writer = setupWriter(reader, outPath);
+ }
+ VectorizedRowBatch batch = reader.getSchema().createRowBatchV2();
+ RecordReader rows = reader.rows();
+ while (rows.nextBatch(batch)) {
+ if (batch != null) {
+ writer.addRowBatch(batch);
+ }
+ }
+ rows.close();
+ }
+ } finally {
+ if (writer != null) {
+ writer.close();
+ }
+ }
Review Comment:
If we create a writer irrespective of number of readers in try with
resources block then a writer will always be created and this may create an
empty file (if readers are not present).
Issue Time Tracking
-------------------
Worklog Id: (was: 837804)
Time Spent: 3h (was: 2h 50m)
> Merge delta files instead of running a query in major/minor compaction
> ----------------------------------------------------------------------
>
> Key: HIVE-22977
> URL: https://issues.apache.org/jira/browse/HIVE-22977
> Project: Hive
> Issue Type: Improvement
> Reporter: László Pintér
> Assignee: Sourabh Badhya
> Priority: Major
> Labels: pull-request-available
> Attachments: HIVE-22977.01.patch, HIVE-22977.02.patch
>
> Time Spent: 3h
> Remaining Estimate: 0h
>
> [Compaction Optimiziation]
> We should analyse the possibility to move a delta file instead of running a
> major/minor compaction query.
> Please consider the following use cases:
> - full acid table but only insert queries were run. This means that no
> delete delta directories were created. Is it possible to merge the delta
> directory contents without running a compaction query?
> - full acid table, initiating queries through the streaming API. If there
> are no abort transactions during the streaming, is it possible to merge the
> delta directory contents without running a compaction query?
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