aokolnychyi commented on code in PR #55518: URL: https://github.com/apache/spark/pull/55518#discussion_r4428927820
########## sql/catalyst/src/main/java/org/apache/spark/sql/connector/write/SupportsColumnUpdates.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.spark.sql.connector.write; + +import org.apache.spark.annotation.Experimental; +import org.apache.spark.sql.connector.expressions.NamedReference; + +/** + * A mix-in interface for {@link RowLevelOperation}. Data sources can implement this interface to + * receive a narrow row containing only the columns declared via {@link #requiredDataAttributes()} + * for updated, copied, and reinserted records, instead of the full table row. + * <p> + * When {@link LogicalWriteInfo#columnUpdateSchema()} is present, updated, copied, and reinserted + * rows follow it: group-based operations receive them through + * {@link DataWriter#writeColumnUpdate(Object, Object)} or + * {@link DataWriter#writeColumnUpdate(Object)}, and operations that mix in {@link SupportsDelta} + * through {@link DeltaWriter#update} and {@link DeltaWriter#reinsert}. Rows the command inserts + * always follow {@link LogicalWriteInfo#schema()} and arrive through + * {@link DataWriter#write(Object)} and {@link DeltaWriter#insert}. When + * {@link LogicalWriteInfo#columnUpdateSchema()} is absent, every row follows + * {@link LogicalWriteInfo#schema()}, as for any other operation. Connectors must decide which + * layout to expect by whether {@link LogicalWriteInfo#columnUpdateSchema()} is present, not by + * the command. A builder that wants full-width rows for some command can check + * {@link RowLevelOperationInfo#command()} and build an operation without this mix-in. Currently + * Spark narrows only UPDATE. + * <p> + * The scan builder returned by {@link #newScanBuilder} should implement Review Comment: In this particular sentence, I am not sure referencing a particular scan API is the right call. We may evolve it in the future. I'd just say that scans must support schema pruning. -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
