PetarVasiljevic-DB commented on code in PR #50921: URL: https://github.com/apache/spark/pull/50921#discussion_r2192732818
########## sql/catalyst/src/main/java/org/apache/spark/sql/connector/read/SupportsPushDownJoin.java: ########## @@ -0,0 +1,83 @@ +/* + * 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.connector.read; + +import org.apache.spark.annotation.Evolving; +import org.apache.spark.sql.connector.expressions.filter.Predicate; +import org.apache.spark.sql.connector.join.JoinType; + +/** + * A mix-in interface for {@link ScanBuilder}. Data sources can implement this interface to + * push down join operators. + * + * @since 4.1.0 + */ +@Evolving +public interface SupportsPushDownJoin extends ScanBuilder { + /** + * Returns true if the other side of the join is compatible with the + * current {@code SupportsPushDownJoin} for a join push down, meaning both sides can be + * processed together within the same underlying data source. + * <br> + * <br> + * For example, JDBC connectors are compatible if they use the same + * host, port, username, and password. + */ + boolean isOtherSideCompatibleForJoin(SupportsPushDownJoin other); + + /** + * Pushes down the join of the current {@code SupportsPushDownJoin} and the other side of join + * {@code SupportsPushDownJoin}. + * + * @param other {@code SupportsPushDownJoin} that this {@code SupportsPushDownJoin} + * gets joined with. + * @param joinType the type of join. + * @param leftSideRequiredColumnWithAliases required output of the left side {@code SupportsPushDownJoin} + * @param rightSideRequiredColumnWithAliases required output of the right side {@code SupportsPushDownJoin} + * @param condition join condition. Columns are named after the specified aliases in + * {@code leftSideRequiredColumnWithAliases} and {@code rightSideRequiredColumnWithAliases} + * @return True if join has been successfully pushed down. + */ + boolean pushDownJoin( + SupportsPushDownJoin other, + JoinType joinType, + ColumnWithAlias[] leftSideRequiredColumnWithAliases, + ColumnWithAlias[] rightSideRequiredColumnWithAliases, + Predicate condition + ); + + /** + * A helper class used when there are duplicated names coming from 2 sides of the join + * operator. + * <br> + * Holds information of original output name and the alias of the new output. + */ + class ColumnWithAlias { Review Comment: done -- 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: reviews-unsubscr...@spark.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org
