nastra commented on code in PR #13933: URL: https://github.com/apache/iceberg/pull/13933#discussion_r2349140851
########## api/src/main/java/org/apache/iceberg/stats/StatsUtil.java: ########## @@ -0,0 +1,172 @@ +/* + * 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.iceberg.stats; + +import static org.apache.iceberg.types.Types.NestedField.optional; + +import java.util.Comparator; +import java.util.List; +import java.util.Objects; +import java.util.stream.Collectors; +import org.apache.iceberg.Schema; +import org.apache.iceberg.relocated.com.google.common.collect.Lists; +import org.apache.iceberg.types.Type; +import org.apache.iceberg.types.TypeUtil; +import org.apache.iceberg.types.Types; + +public class StatsUtil { + private static final int NUM_STATS_PER_COLUMN = 200; + static final int RESERVED_FIELD_IDS = 200; + static final int DATA_SPACE_FIELD_ID_START = 10_000; + static final int METADATA_SPACE_FIELD_ID_START = 1_417_000_000; + static final int RESERVED_FIELD_IDS_START = Integer.MAX_VALUE - RESERVED_FIELD_IDS; + + private StatsUtil() {} + + public static int statsFieldIdFor(int fieldId) { + int idSpaceStart = DATA_SPACE_FIELD_ID_START; + int id = fieldId; + if (fieldId >= RESERVED_FIELD_IDS_START) { + // this is a reserved field ID, which uses a different calculation + idSpaceStart = METADATA_SPACE_FIELD_ID_START; + id = RESERVED_FIELD_IDS - (Integer.MAX_VALUE - fieldId); + } + + long finalId = idSpaceStart + NUM_STATS_PER_COLUMN * (long) id; + if (finalId < 0 + || finalId > RESERVED_FIELD_IDS_START + || (finalId >= METADATA_SPACE_FIELD_ID_START + && idSpaceStart != METADATA_SPACE_FIELD_ID_START)) { + // ID overflows + return -1; + } + + return (int) finalId; + } + + public static int fieldIdFor(int statsFieldId) { + if (statsFieldId < 0 || statsFieldId % NUM_STATS_PER_COLUMN != 0) { + return -1; + } + + int finalId; + if (statsFieldId < METADATA_SPACE_FIELD_ID_START) { + finalId = (statsFieldId - DATA_SPACE_FIELD_ID_START) / NUM_STATS_PER_COLUMN; + } else { + // this is a reserved field ID, which uses a different calculation + finalId = + statsFieldId + - RESERVED_FIELD_IDS + + (Integer.MAX_VALUE - statsFieldId) + + (statsFieldId - METADATA_SPACE_FIELD_ID_START) / NUM_STATS_PER_COLUMN; + } + + return Math.max(-1, finalId); + } + + public static Types.NestedField contentStatsFor(Schema schema) { + return TypeUtil.visit(schema, new ContentStatsSchemaVisitor()); + } + + private static Types.StructType contentStatsFor(Type type, int id) { + int fieldId = id; + + return Types.StructType.of( + optional(fieldId++, "column_size", Types.LongType.get(), "Total size on disk"), + optional( + fieldId++, + "value_count", + Types.LongType.get(), + "Total value count, including null and NaN"), + optional(fieldId++, "nan_value_count", Types.LongType.get(), "Total NaN value count"), + optional(fieldId++, "null_value_count", Types.LongType.get(), "Total null value count"), + optional(fieldId++, "lower_bound", type, "Lower bound"), + optional(fieldId, "upper_bound", type, "Upper bound")); Review Comment: makes sense -- 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: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org
