rdblue commented on a change in pull request #35395: URL: https://github.com/apache/spark/pull/35395#discussion_r810699576
########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/RewriteDeleteFromTable.scala ########## @@ -0,0 +1,84 @@ +/* + * 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.catalyst.analysis + +import org.apache.spark.sql.AnalysisException +import org.apache.spark.sql.catalyst.expressions.{EqualNullSafe, Expression, Literal, Not} +import org.apache.spark.sql.catalyst.plans.logical.{DeleteFromTable, Filter, LogicalPlan, ReplaceData} +import org.apache.spark.sql.connector.catalog.{SupportsDelete, SupportsRowLevelOperations} +import org.apache.spark.sql.connector.write.RowLevelOperation.Command.DELETE +import org.apache.spark.sql.connector.write.RowLevelOperationTable +import org.apache.spark.sql.execution.datasources.v2.DataSourceV2Relation + +/** + * Assigns a rewrite plan for v2 tables that support rewriting data to handle DELETE statements. + * + * If a table implements [[SupportsDelete]] and [[SupportsRowLevelOperations]], this rule assigns + * a rewrite plan but the optimizer will check whether this particular DELETE statement can be + * handled by simply passing delete filters to the connector. If yes, the optimizer will then + * discard the rewrite plan. + */ +object RewriteDeleteFromTable extends RewriteRowLevelCommand { + + override def apply(plan: LogicalPlan): LogicalPlan = plan resolveOperators { + case d @ DeleteFromTable(aliasedTable, cond, None) if d.resolved => + EliminateSubqueryAliases(aliasedTable) match { + case r @ DataSourceV2Relation(tbl: SupportsRowLevelOperations, _, _, _, _) => + val operation = buildRowLevelOperation(tbl, DELETE) + val table = RowLevelOperationTable(tbl, operation) + val deleteCond = cond.getOrElse(Literal.TrueLiteral) + val rewritePlan = buildReplaceDataPlan(r, table, deleteCond) + // keep the original relation in DELETE to attempt deleting using filters + DeleteFromTable(r, cond, Some(rewritePlan)) + + case DataSourceV2Relation(_: SupportsDelete, _, _, _, _) => + // don't assign a rewrite plan as the table supports deletes only with filters + d + + case DataSourceV2Relation(t, _, _, _, _) => + throw new AnalysisException(s"Table $t does not support DELETE statements") + + case _ => + d + } + } + + // build a rewrite plan for sources that support replacing groups of data (e.g. files, partitions) + private def buildReplaceDataPlan( + relation: DataSourceV2Relation, + operationTable: RowLevelOperationTable, + cond: Expression): ReplaceData = { + + // resolve all required metadata attrs (e.g. may be needed for grouping data on write) Review comment: You might give a clearer example: ```scala // resolve all required metadata attrs that may be used for grouping data on write (e.g., by JDBC shard/host) ``` -- 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]
