aokolnychyi commented on a change in pull request #3764: URL: https://github.com/apache/iceberg/pull/3764#discussion_r772548715
########## File path: spark/v3.2/spark-extensions/src/main/scala/org/apache/spark/sql/catalyst/analysis/AssignmentAlignmentSupport.scala ########## @@ -0,0 +1,250 @@ +/* + * 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.SQLConfHelper +import org.apache.spark.sql.catalyst.expressions.Alias +import org.apache.spark.sql.catalyst.expressions.AnsiCast +import org.apache.spark.sql.catalyst.expressions.AttributeReference +import org.apache.spark.sql.catalyst.expressions.Cast +import org.apache.spark.sql.catalyst.expressions.CreateNamedStruct +import org.apache.spark.sql.catalyst.expressions.Expression +import org.apache.spark.sql.catalyst.expressions.ExtractValue +import org.apache.spark.sql.catalyst.expressions.GetStructField +import org.apache.spark.sql.catalyst.expressions.Literal +import org.apache.spark.sql.catalyst.expressions.NamedExpression +import org.apache.spark.sql.catalyst.plans.logical.Assignment +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.util.CharVarcharUtils +import org.apache.spark.sql.internal.SQLConf.StoreAssignmentPolicy +import org.apache.spark.sql.types.DataType +import org.apache.spark.sql.types.StructField +import org.apache.spark.sql.types.StructType +import scala.collection.mutable + +trait AssignmentAlignmentSupport extends CastSupport { + + self: SQLConfHelper => + + private case class ColumnUpdate(ref: Seq[String], expr: Expression) + + /** + * Checks whether assignments are aligned and match table columns. + * + * @param table a target table + * @param assignments assignments to check + * @return true if the assignments are aligned + */ + protected def aligned(table: LogicalPlan, assignments: Seq[Assignment]): Boolean = { + val sameSize = table.output.size == assignments.size + sameSize && table.output.zip(assignments).forall { case (attr, assignment) => + val key = assignment.key + val value = assignment.value + asAssignmentRef(attr) == asAssignmentRef(key) && attr.dataType == value.dataType + } + } + + /** + * Aligns assignments to match table columns. + * <p> + * This method processes and reorders given assignments so that each target column gets + * an expression it should be set to. If a column does not have a matching assignment, + * it will be set to its current value. For example, if one passes a table with columns c1, c2 + * and an assignment c2 = 1, this method will return c1 = c1, c2 = 1. + * <p> + * This method also handles updates to nested columns. If there is an assignment to a particular + * nested field, this method will construct a new struct with one field updated + * preserving other fields that have not been modified. For example, if one passes a table with + * columns c1, c2 where c2 is a struct with fields n1 and n2 and an assignment c2.n2 = 1, + * this method will return c1 = c1, c2 = struct(c2.n1, 1). + * + * @param table a target table + * @param assignments assignments to align + * @return aligned assignments that match table columns + */ + protected def alignAssignments( + table: LogicalPlan, + assignments: Seq[Assignment]): Seq[Assignment] = { + + val columnUpdates = assignments.map(a => ColumnUpdate(asAssignmentRef(a.key), a.value)) + val outputExprs = applyUpdates(table.output, columnUpdates) + outputExprs.zip(table.output).map { + case (expr, attr) => toAssignment(attr, expr) + } + } + + protected def toAssignment(key: Expression, value: Expression): Assignment = { Review comment: I added `AssignmentUtils` with a separate method dedicated to this functionality. -- 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]
