ldudas-marx commented on code in PR #16262: URL: https://github.com/apache/iceberg/pull/16262#discussion_r3241903345
########## api/src/main/java/org/apache/iceberg/transforms/Cast.java: ########## @@ -0,0 +1,1010 @@ +/* + * 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.transforms; + +import java.math.BigDecimal; +import java.math.RoundingMode; +import java.nio.ByteBuffer; +import java.util.List; +import java.util.Objects; +import org.apache.iceberg.expressions.BoundLiteralPredicate; +import org.apache.iceberg.expressions.BoundPredicate; +import org.apache.iceberg.expressions.BoundSetPredicate; +import org.apache.iceberg.expressions.Expressions; +import org.apache.iceberg.expressions.UnboundPredicate; +import org.apache.iceberg.relocated.com.google.common.base.Preconditions; +import org.apache.iceberg.types.Type; +import org.apache.iceberg.types.Types; +import org.apache.iceberg.util.DateTimeUtil; +import org.apache.iceberg.util.SerializableFunction; + +/** + * A transform that casts values from one type to another. + * + * <p>This transform performs explicit type conversions, similar to SQL CAST operations. It supports + * casting between compatible types with appropriate handling of overflow, precision loss, and null + * values. + * + * @param <S> the source type + * @param <T> the target type + */ +class Cast<S, T> implements Transform<S, T> { + private static final long MICROS_PER_DAY = 86_400_000_000L; + private static final long NANOS_PER_MICRO = 1_000L; + private static final long NANOS_PER_DAY = 86_400_000_000_000L; + + private final Type targetType; + + private Cast(Type targetType) { + Preconditions.checkNotNull(targetType, "Target type cannot be null"); + this.targetType = targetType; + } + + @SuppressWarnings("unchecked") + static <S, T> Cast<S, T> get(Type targetType) { + return new Cast<>(targetType); + } + + @Override + public SerializableFunction<S, T> bind(Type sourceType) { + return new CastFunction<>(sourceType, targetType); + } + + @Override + public boolean canTransform(Type sourceType) { + return isValidCast(sourceType, targetType); + } + + @Override + public Type getResultType(Type sourceType) { + Preconditions.checkArgument( + canTransform(sourceType), "Cannot cast from %s to %s", sourceType, targetType); + return targetType; + } + + @Override + public boolean preservesOrder() { + // Cast order preservation depends on source and target types. + return false; + } + + @Override + public boolean preservesOrder(Type sourceType) { + Type.TypeID source = sourceType.typeId(); + Type.TypeID target = targetType.typeId(); + + if (source == target) { + return true; + } + + if (isNumeric(source) && isNumeric(target)) { + return true; + } + + if (isDateTimeOrderPreserving(source, target)) { + return true; + } + + return false; + } + + private static boolean isNumeric(Type.TypeID type) { + switch (type) { + case INTEGER: + case LONG: + case FLOAT: + case DOUBLE: + case DECIMAL: + return true; + default: + return false; + } + } + + private static boolean isDateTimeOrderPreserving(Type.TypeID source, Type.TypeID target) { + switch (source) { + case INTEGER: + return target == Type.TypeID.DATE; + + case LONG: + return target == Type.TypeID.TIME + || target == Type.TypeID.TIMESTAMP + || target == Type.TypeID.TIMESTAMP_NANO + || target == Type.TypeID.DATE; + + case DATE: + return target == Type.TypeID.TIMESTAMP + || target == Type.TypeID.TIMESTAMP_NANO + || target == Type.TypeID.STRING; + + case TIME: + return target == Type.TypeID.LONG || target == Type.TypeID.STRING; + + case TIMESTAMP: + return target == Type.TypeID.DATE + || target == Type.TypeID.TIMESTAMP_NANO + || target == Type.TypeID.LONG; + + case TIMESTAMP_NANO: + return target == Type.TypeID.DATE + || target == Type.TypeID.TIMESTAMP + || target == Type.TypeID.LONG; + + case STRING: + return target == Type.TypeID.DATE; + + default: + return false; + } + } + + @Override + public UnboundPredicate<T> project(String name, BoundPredicate<S> predicate) { Review Comment: If Cast is not supported in partitioning this is dead code. I would just throw UnsupportedOperationException here. ########## api/src/main/java/org/apache/iceberg/transforms/Identity.java: ########## @@ -146,16 +149,31 @@ public UnboundPredicate<T> project(String name, BoundPredicate<T> predicate) { @Override public UnboundPredicate<T> projectStrict(String name, BoundPredicate<T> predicate) { + // Reconstruct the unbound term with the partition column name + UnboundTerm<T> term = unboundTerm(name, predicate.term()); + if (predicate.isUnaryPredicate()) { - return Expressions.predicate(predicate.op(), name); + return Expressions.predicate(predicate.op(), term); } else if (predicate.isLiteralPredicate()) { - return Expressions.predicate(predicate.op(), name, predicate.asLiteralPredicate().literal()); + return Expressions.predicate(predicate.op(), term, predicate.asLiteralPredicate().literal()); } else if (predicate.isSetPredicate()) { - return Expressions.predicate(predicate.op(), name, predicate.asSetPredicate().literalSet()); + return Expressions.predicate(predicate.op(), term, predicate.asSetPredicate().literalSet()); } return null; } + @SuppressWarnings("unchecked") + private <S> UnboundTerm<S> unboundTerm(String name, BoundTerm<S> bound) { Review Comment: ExpressionUtil.unbind(term) already implements this functionality. -- This is an automated message from the Apache Git Service. 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