rdblue commented on a change in pull request #3661: URL: https://github.com/apache/iceberg/pull/3661#discussion_r762617205
########## File path: spark/v3.2/spark-extensions/src/main/scala/org/apache/spark/sql/catalyst/analysis/RewriteDeleteFromTable.scala ########## @@ -0,0 +1,101 @@ +/* + * 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 +import org.apache.spark.sql.catalyst.expressions.Expression +import org.apache.spark.sql.catalyst.expressions.Literal +import org.apache.spark.sql.catalyst.expressions.Not +import org.apache.spark.sql.catalyst.plans.logical.DeleteFromIcebergTable +import org.apache.spark.sql.catalyst.plans.logical.Filter +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.plans.logical.ReplaceData +import org.apache.spark.sql.connector.catalog.SupportsDelete +import org.apache.spark.sql.connector.iceberg.catalog.SupportsRowLevelOperations +import org.apache.spark.sql.connector.iceberg.write.RowLevelOperation.Command.DELETE +import org.apache.spark.sql.connector.iceberg.write.SupportsDelta +import org.apache.spark.sql.connector.write.RowLevelOperationTable +import org.apache.spark.sql.execution.datasources.v2.DataSourceV2Relation +import org.apache.spark.sql.types.BooleanType + +/** + * Assigns a rewrite plan for v2 tables that support rewriting data to handle DELETE statements. + * + * If a table implements SupportsDelete and SupportsRowLevelOperations, we assign 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 @ DeleteFromIcebergTable(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 rewritePlan = operation match { + case _: SupportsDelta => + throw new AnalysisException("Delta operations are currently not supported") + case _ => + buildReplaceDataPlan(r, table, cond) + } + // keep the original relation in DELETE to try deleting using filters + DeleteFromIcebergTable(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, + table: RowLevelOperationTable, + cond: Option[Expression]): ReplaceData = { + + // resolve all needed attrs (e.g. metadata attrs for grouping data on write) + val rowAttrs = relation.output + val metadataAttrs = resolveRequiredMetadataAttrs(relation, table.operation) + + // construct a scan relation and include all required metadata columns + val scanAttrs = dedupAttrs(rowAttrs ++ metadataAttrs) + val scanRelation = relation.copy(table = table, output = scanAttrs) + + // construct a plan that contains unmatched rows in matched groups that must be carried over + // such rows do not match the condition but have to be copied over as the source can replace + // only groups of rows + val deleteCond = cond.getOrElse(Literal.TrueLiteral) Review comment: This seems odd to me. If there is no condition, why add one and continue the rewrite? We know that `true` can be done in metadata, so we could check this above and avoid building the plan entirely. -- 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]
