cmathiesen commented on a change in pull request #1326: URL: https://github.com/apache/iceberg/pull/1326#discussion_r476281343
########## File path: mr/src/main/java/org/apache/iceberg/mr/hive/HiveIcebergFilterFactory.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.mr.hive; + +import java.math.BigDecimal; +import java.sql.Date; +import java.sql.Timestamp; +import java.util.List; +import java.util.concurrent.TimeUnit; +import java.util.stream.Collectors; +import org.apache.hadoop.hive.ql.io.sarg.ExpressionTree; +import org.apache.hadoop.hive.ql.io.sarg.PredicateLeaf; +import org.apache.hadoop.hive.ql.io.sarg.SearchArgument; +import org.apache.hadoop.hive.serde2.io.HiveDecimalWritable; +import org.apache.iceberg.expressions.Expression; +import org.apache.iceberg.expressions.Expressions; + +import static org.apache.iceberg.expressions.Expressions.and; +import static org.apache.iceberg.expressions.Expressions.equal; +import static org.apache.iceberg.expressions.Expressions.greaterThanOrEqual; +import static org.apache.iceberg.expressions.Expressions.in; +import static org.apache.iceberg.expressions.Expressions.isNull; +import static org.apache.iceberg.expressions.Expressions.lessThan; +import static org.apache.iceberg.expressions.Expressions.lessThanOrEqual; +import static org.apache.iceberg.expressions.Expressions.not; +import static org.apache.iceberg.expressions.Expressions.or; + + +public class HiveIcebergFilterFactory { + + private HiveIcebergFilterFactory() {} + + public static Expression generateFilterExpression(SearchArgument sarg) { + return translate(sarg.getExpression(), sarg.getLeaves()); + } + + /** + * Recursive method to traverse down the ExpressionTree to evaluate each expression and its leaf nodes. + * @param tree Current ExpressionTree where the 'top' node is being evaluated. + * @param leaves List of all leaf nodes within the tree. + * @return Expression that is translated from the Hive SearchArgument. + */ + private static Expression translate(ExpressionTree tree, List<PredicateLeaf> leaves) { + List<ExpressionTree> childNodes = tree.getChildren(); + switch (tree.getOperator()) { + case OR: + Expression orResult = Expressions.alwaysFalse(); + for (ExpressionTree child : childNodes) { + orResult = or(orResult, translate(child, leaves)); + } + return orResult; + case AND: + Expression result = Expressions.alwaysTrue(); + for (ExpressionTree child : childNodes) { + result = and(result, translate(child, leaves)); + } + return result; + case NOT: + return not(translate(childNodes.get(0), leaves)); + case LEAF: + return translateLeaf(leaves.get(tree.getLeaf())); + case CONSTANT: + throw new UnsupportedOperationException("CONSTANT operator is not supported"); + default: + throw new UnsupportedOperationException("Unknown operator: " + tree.getOperator()); + } + } + + /** + * Translate leaf nodes from Hive operator to Iceberg operator. + * @param leaf Leaf node + * @return Expression fully translated from Hive PredicateLeaf + */ + private static Expression translateLeaf(PredicateLeaf leaf) { + String column = leaf.getColumnName(); + switch (leaf.getOperator()) { + case EQUALS: + return equal(column, leafToLiteral(leaf)); + case LESS_THAN: + return lessThan(column, leafToLiteral(leaf)); + case LESS_THAN_EQUALS: + return lessThanOrEqual(column, leafToLiteral(leaf)); + case IN: + return in(column, leafToLiteralList(leaf)); + case BETWEEN: + List<Object> icebergLiterals = leafToLiteralList(leaf); + return and(greaterThanOrEqual(column, icebergLiterals.get(0)), + lessThanOrEqual(column, icebergLiterals.get(1))); + case IS_NULL: + return isNull(column); + default: + throw new UnsupportedOperationException("Unknown operator: " + leaf.getOperator()); + } + } + + private static Object leafToLiteral(PredicateLeaf leaf) { + switch (leaf.getType()) { + case LONG: + case BOOLEAN: + case STRING: + case FLOAT: + return leaf.getLiteral(); + case DATE: + //Hive converts a Date type to a Timestamp internally when retrieving literal + return timestampToDateString((Timestamp) leaf.getLiteral()); + case DECIMAL: + return hiveDecimalToBigDecimal((HiveDecimalWritable) leaf.getLiteral()); + case TIMESTAMP: + return timestampToUnixEpoch((Timestamp) leaf.getLiteral()); + + default: + throw new UnsupportedOperationException("Unknown type: " + leaf.getType()); + } + } + + private static List<Object> leafToLiteralList(PredicateLeaf leaf) { + switch (leaf.getType()) { + case LONG: + case BOOLEAN: + case FLOAT: + case STRING: + return leaf.getLiteralList(); + case DATE: + return leaf.getLiteralList().stream().map(value -> dateToString((Date) value)) + .collect(Collectors.toList()); + case DECIMAL: + return leaf.getLiteralList().stream() + .map(value -> hiveDecimalToBigDecimal((HiveDecimalWritable) value)) + .collect(Collectors.toList()); + case TIMESTAMP: + return leaf.getLiteralList().stream() + .map(value -> timestampToUnixEpoch((Timestamp) value)) + .collect(Collectors.toList()); + default: + throw new UnsupportedOperationException("Unknown type: " + leaf.getType()); + } + } + + private static String timestampToDateString(Timestamp timestamp) { + return timestamp.toLocalDateTime().toLocalDate().toString(); + } + + private static String dateToString(Date date) { + return date.toLocalDate().toString(); + } + + private static BigDecimal hiveDecimalToBigDecimal(HiveDecimalWritable hiveDecimalWritable) { + return hiveDecimalWritable.getHiveDecimal().bigDecimalValue().setScale(hiveDecimalWritable.scale()); + } + + private static long timestampToUnixEpoch(Timestamp timestamp) { + return timestamp.toInstant().getEpochSecond() * TimeUnit.SECONDS.toMicros(1) + + timestamp.getNanos() / TimeUnit.MICROSECONDS.toNanos(1); Review comment: Ah yep, probably should have spotted that one 😅 ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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