Github user tejasapatil commented on a diff in the pull request:
https://github.com/apache/spark/pull/16985#discussion_r116163888
--- Diff:
sql/core/src/main/scala/org/apache/spark/sql/execution/joins/ReorderJoinPredicates.scala
---
@@ -0,0 +1,93 @@
+/*
+ * 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.spark.sql.execution.joins
+
+import scala.collection.mutable.ArrayBuffer
+
+import org.apache.spark.sql.catalyst.expressions.Expression
+import org.apache.spark.sql.catalyst.plans.physical.{HashPartitioning,
Partitioning}
+import org.apache.spark.sql.catalyst.rules.Rule
+import org.apache.spark.sql.execution.SparkPlan
+
+/**
+ * When the physical operators are created for JOIN, the ordering of join
keys is based on order
+ * in which the join keys appear in the user query. That might not match
with the output
+ * partitioning of the join node's children (thus leading to extra sort /
shuffle being
+ * introduced). This rule will change the ordering of the join keys to
match with the
+ * partitioning of the join nodes' children.
+ */
+class ReorderJoinPredicates extends Rule[SparkPlan] {
+ private def reorderJoinKeys(
+ leftKeys: Seq[Expression],
+ rightKeys: Seq[Expression],
+ leftPartitioning: Partitioning,
+ rightPartitioning: Partitioning): (Seq[Expression], Seq[Expression])
= {
+
+ def reorder(expectedOrderOfKeys: Seq[Expression],
--- End diff --
fixed this.
PS: I always manually fix this. If there is some predefined checkstyle
which I could import in Intelij, that will save this trouble for me and
reviewers.
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org
