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https://issues.apache.org/jira/browse/HIVE-23006?focusedWorklogId=403499&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-403499
]
ASF GitHub Bot logged work on HIVE-23006:
-----------------------------------------
Author: ASF GitHub Bot
Created on: 14/Mar/20 20:09
Start Date: 14/Mar/20 20:09
Worklog Time Spent: 10m
Work Description: jcamachor commented on pull request #952: HIVE-23006
ProbeDecode compiler support
URL: https://github.com/apache/hive/pull/952#discussion_r392609447
##########
File path:
ql/src/java/org/apache/hadoop/hive/ql/optimizer/ProbeDecodeOptimizer.java
##########
@@ -0,0 +1,139 @@
+/*
+ * 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.optimizer;
+
+import org.apache.hadoop.hive.ql.exec.MapJoinOperator;
+import org.apache.hadoop.hive.ql.exec.Operator;
+import org.apache.hadoop.hive.ql.exec.TableScanOperator;
+import org.apache.hadoop.hive.ql.parse.ParseContext;
+import org.apache.hadoop.hive.ql.parse.SemanticException;
+import org.apache.hadoop.hive.ql.plan.ExprNodeColumnDesc;
+import org.apache.hadoop.hive.ql.plan.ExprNodeDesc;
+import org.apache.hadoop.hive.ql.plan.MapJoinDesc;
+import
org.apache.hadoop.hive.serde2.objectinspector.PrimitiveObjectInspector.PrimitiveCategory;
+import org.apache.hadoop.hive.serde2.typeinfo.PrimitiveTypeInfo;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.ArrayList;
+import java.util.Deque;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * <p> The goal of this rule is to find suitable table scan operators that
could reduce the
+ * number of rows decoded at runtime using extra available information.
+ *
+ * <p> First the rule checks all the available MapJoin operators that could
propagate the
+ * smaller HashTable on the probing side (where TS is) to filter-out rows that
would
+ * never match. To do so the HashTable information is pushed down to the TS
properties.
+ * If the a single TS is used by multiple operators (shared-word), this rule
Review comment:
typo: word -> work
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Issue Time Tracking
-------------------
Worklog Id: (was: 403499)
Time Spent: 20m (was: 10m)
> Compiler support for Probe MapJoin
> ----------------------------------
>
> Key: HIVE-23006
> URL: https://issues.apache.org/jira/browse/HIVE-23006
> Project: Hive
> Issue Type: Sub-task
> Reporter: Panagiotis Garefalakis
> Assignee: Panagiotis Garefalakis
> Priority: Major
> Labels: pull-request-available
> Time Spent: 20m
> Remaining Estimate: 0h
>
> The decision of pushing down information to the Record reader (potentially
> reducing decoding time by row-level filtering) should be done at query
> compilation time.
> This patch adds an extra optimisation step with the goal of finding Table
> Scan operators that could reduce the number of rows decoded at runtime using
> extra available information.
> It currently looks for all the available MapJoin operators that could use the
> smaller HashTable on the probing side (where TS is) to filter-out rows that
> would never match.
> To do so the HashTable information is pushed down to the TS properties and
> then propagated as part of MapWork.
> If the a single TS is used by multiple operators (shared-word), this rule can
> not be applied.
> This rule can be extended to support static filter expressions like:
> _select * from sales where sold_state = 'PR';_
> This optimisation manly targets the Tez execution engine running on Llap.
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