jonvex commented on code in PR #14120: URL: https://github.com/apache/hudi/pull/14120#discussion_r2446137148
########## hudi-client/hudi-spark-client/src/main/java/org/apache/hudi/common/ParquetTimestampUtils.java: ########## @@ -0,0 +1,170 @@ +/* + * 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.hudi.common; + +import org.apache.parquet.schema.GroupType; +import org.apache.parquet.schema.LogicalTypeAnnotation; +import org.apache.parquet.schema.MessageType; +import org.apache.parquet.schema.PrimitiveType; +import org.apache.parquet.schema.Type; + +import java.util.HashSet; +import java.util.List; +import java.util.Set; + +/** + * Utility class for handling Parquet timestamp precision conversions. + */ +public class ParquetTimestampUtils { + + /** + * Identifies columns that need multiplication by 1000 when converting from TIMESTAMP_MICROS to TIMESTAMP_MILLIS. + * + * This method compares two Parquet schemas and identifies fields where: + * - The file schema has TIMESTAMP_MICROS precision + * - The table schema has TIMESTAMP_MILLIS precision + * + * @param fileSchema The Parquet schema from the file (source) + * @param tableSchema The Parquet schema from the table (target) + * @return Set of column paths (e.g., "timestamp", "metadata.created_at") that need multiplication + */ + public static Set<String> findColumnsToMultiply(MessageType fileSchema, MessageType tableSchema) { + Set<String> columnsToMultiply = new HashSet<>(); + compareTypes(fileSchema, tableSchema, "", columnsToMultiply); + return columnsToMultiply; + } + + /** + * Recursively compares two Parquet types and identifies timestamp precision mismatches. + * + * @param fileType The type from the file schema + * @param tableType The type from the table schema + * @param path The current column path (dotted notation for nested fields) + * @param columnsToMultiply Set to accumulate columns that need multiplication + */ + private static void compareTypes(Type fileType, Type tableType, String path, Set<String> columnsToMultiply) { + // Handle group types (structs) + if (!fileType.isPrimitive() && !tableType.isPrimitive()) { + GroupType fileGroup = fileType.asGroupType(); + GroupType tableGroup = tableType.asGroupType(); + + List<Type> fileFields = fileGroup.getFields(); + + for (Type fileField : fileFields) { + String fieldName = fileField.getName(); + + // Check if field exists in table schema + if (tableGroup.containsField(fieldName)) { + Type tableField = tableGroup.getType(fieldName); + String nestedPath = path.isEmpty() ? fieldName : path + "." + fieldName; + compareTypes(fileField, tableField, nestedPath, columnsToMultiply); + } + // If field doesn't exist in table, skip it + } + return; + } + + // Handle primitive types + if (fileType.isPrimitive() && tableType.isPrimitive()) { + if (isTimestampMicros(fileType) && isTimestampMillis(tableType)) { + columnsToMultiply.add(path); + } else if (isLong(fileType) && isLocalTimestampMillis(tableType)) { + columnsToMultiply.add(path); Review Comment: It's not new, I brought it up a bunch of times. In the doc we have rows to show what is happening -- 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]
