ramitg254 commented on code in PR #5715: URL: https://github.com/apache/hive/pull/5715#discussion_r2060238254
########## ql/src/java/org/apache/hadoop/hive/ql/ddl/table/column/drop/AlterTableDropColumnOperation.java: ########## @@ -0,0 +1,93 @@ +/* + * 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.hadoop.hive.ql.ddl.table.column.drop; + +import com.google.common.collect.ImmutableSet; +import org.apache.hadoop.hive.metastore.api.FieldSchema; +import org.apache.hadoop.hive.metastore.api.StorageDescriptor; +import org.apache.hadoop.hive.ql.ErrorMsg; +import org.apache.hadoop.hive.ql.ddl.DDLOperationContext; +import org.apache.hadoop.hive.ql.ddl.table.AbstractAlterTableOperation; +import org.apache.hadoop.hive.ql.ddl.table.AlterTableUtils; +import org.apache.hadoop.hive.ql.io.orc.OrcSerde; +import org.apache.hadoop.hive.ql.io.parquet.serde.ParquetHiveSerDe; +import org.apache.hadoop.hive.ql.metadata.HiveException; +import org.apache.hadoop.hive.ql.metadata.Partition; +import org.apache.hadoop.hive.ql.metadata.Table; +import org.apache.hadoop.hive.serde2.MetadataTypedColumnsetSerDe; +import org.apache.hadoop.hive.serde2.avro.AvroSerdeUtils; +import org.apache.hadoop.hive.serde2.columnar.ColumnarSerDe; +import org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe; + +import java.util.ArrayList; +import java.util.List; +import java.util.Set; + +/** + * Operation process of dropping column. + */ +public class AlterTableDropColumnOperation extends AbstractAlterTableOperation<AlterTableDropColumnDesc> { + + public AlterTableDropColumnOperation(DDLOperationContext context, AlterTableDropColumnDesc desc) { + super(context, desc); + } + + @Override + protected void doAlteration(Table table, Partition partition) throws HiveException { + StorageDescriptor sd = getStorageDescriptor(table, partition); + String serializationLib = sd.getSerdeInfo().getSerializationLib(); + AvroSerdeUtils.handleAlterTableForAvro(context.getConf(), serializationLib, table.getTTable().getParameters()); + + if ("org.apache.hadoop.hive.serde.thrift.columnsetSerDe".equals(serializationLib)) { + context.getConsole().printInfo("Dropping column for columnsetSerDe and changing to LazySimpleSerDe"); + sd.getSerdeInfo().setSerializationLib(LazySimpleSerDe.class.getName()); + } + + boolean isOrcSchemaEvolution = + serializationLib.equals(OrcSerde.class.getName()) && AlterTableUtils.isSchemaEvolutionEnabled(table, + context.getConf()); + if (isOrcSchemaEvolution) { + throw new HiveException(ErrorMsg.CANNOT_DROP_COLUMN, desc.getDbTableName()); + } + + if (ParquetHiveSerDe.isParquetTable(table) && AlterTableUtils.isSchemaEvolutionEnabled(table, + context.getConf()) && !desc.isCascade() && table.isPartitioned()) { + LOG.warn("Cannot drop column from a partitioned parquet table without the CASCADE option"); + throw new HiveException(ErrorMsg.DROP_COLUMN_UNCASCADED, desc.getDbTableName()); + } + + List<FieldSchema> cols = new ArrayList<>(sd.getCols()); + int droppingIndex = -1; + for (int i = 0; i < cols.size(); i++) { Review Comment: I think it shouldn't be right thing to directly alter `sd.getCols()` as it has also `sd.setCols` and `sd.getCols()` returns internal cols directly instead of a copy list, so changed to ``` List<FieldSchema> cols = new ArrayList<>(sd.getCols()); boolean removed = cols.removeIf(col -> col.getName().equalsIgnoreCase(desc.getColName())); ``` -- 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: gitbox-unsubscr...@hive.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: gitbox-unsubscr...@hive.apache.org For additional commands, e-mail: gitbox-h...@hive.apache.org
