snuyanzin commented on code in PR #25763: URL: https://github.com/apache/flink/pull/25763#discussion_r1890709719
########## flink-table/flink-table-runtime/src/main/java/org/apache/flink/table/runtime/functions/scalar/ToTimestampLtzFunction.java: ########## @@ -0,0 +1,128 @@ +/* + * 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.flink.table.runtime.functions.scalar; + +import org.apache.flink.annotation.Internal; +import org.apache.flink.table.data.DecimalData; +import org.apache.flink.table.data.StringData; +import org.apache.flink.table.data.TimestampData; +import org.apache.flink.table.functions.BuiltInFunctionDefinitions; +import org.apache.flink.table.functions.SpecializedFunction; +import org.apache.flink.table.utils.DateTimeUtils; + +import javax.annotation.Nullable; + +/** + * Implementation of {@link BuiltInFunctionDefinitions#TO_TIMESTAMP_LTZ}. + * + * <p>A function that converts various time formats to TIMESTAMP_LTZ type. + * + * <p>Supported function signatures: + * + * <ul> + * <li>{@code TO_TIMESTAMP_LTZ(numeric)} -> TIMESTAMP_LTZ(3) <br> + * Converts numeric epoch time in milliseconds to timestamp with local timezone + * <li>{@code TO_TIMESTAMP_LTZ(numeric, precision)} -> TIMESTAMP_LTZ(precision) <br> + * Converts numeric epoch time to timestamp with specified precision (0 as seconds, 3 as + * milliseconds) + * <li>{@code TO_TIMESTAMP_LTZ(timestamp)} -> TIMESTAMP_LTZ(3) <br> + * Parses string timestamp using default format 'yyyy-MM-dd HH:mm:ss' + * <li>{@code TO_TIMESTAMP_LTZ(timestamp, format)} -> TIMESTAMP_LTZ(3) <br> + * Parses string timestamp using input string of format + * <li>{@code TO_TIMESTAMP_LTZ(timestamp, format, timezone)} -> TIMESTAMP_LTZ(3) <br> + * Parses string timestamp using input strings of format and timezone + * </ul> + * + * <p>Example: + * + * <pre>{@code + * TO_TIMESTAMP_LTZ('2023-01-01 10:00:00')} // Parses string using default format + * TO_TIMESTAMP_LTZ(1234567890123)} // Converts epoch milliseconds + * TO_TIMESTAMP_LTZ(1234567890, 0) // Converts epoch seconds + * TO_TIMESTAMP_LTZ(1234567890123, 3) // Converts epoch milliseconds + * TO_TIMESTAMP_LTZ('2023-01-01 10:00:00') // Parses string using default format + * TO_TIMESTAMP_LTZ('2023-01-01T10:00:00', 'yyyy-MM-dd\'T\'HH:mm:ss')} // Parses string using input format + * TO_TIMESTAMP_LTZ('2023-01-01 10:00:00', 'yyyy-MM-dd HH:mm:ss', 'UTC')} // Parses string using input format and timezone + * }</pre> + */ +@Internal +public class ToTimestampLtzFunction extends BuiltInScalarFunction { + + private static final int DEFAULT_PRECISION = 3; + + public ToTimestampLtzFunction(SpecializedFunction.SpecializedContext context) { + super(BuiltInFunctionDefinitions.TO_TIMESTAMP_LTZ, context); + } + + public @Nullable TimestampData eval(Number epoch, Integer precision) { + if (epoch == null || precision == null) { + return null; + } + if (epoch instanceof Float || epoch instanceof Double) { + return DateTimeUtils.toTimestampData(epoch.doubleValue(), precision); + } + return DateTimeUtils.toTimestampData(epoch.longValue(), precision); + } + + public @Nullable TimestampData eval(DecimalData epoch, Integer precision) { + if (epoch == null || precision == null) { + return null; + } + + return DateTimeUtils.toTimestampData(epoch, precision); + } + + public @Nullable TimestampData eval(Number epoch) { + return eval(epoch, DEFAULT_PRECISION); + } + + public TimestampData eval(DecimalData epoch) { + if (epoch == null) { + return null; + } + + return DateTimeUtils.toTimestampData(epoch); + } + + public @Nullable TimestampData eval(StringData timestamp) { Review Comment: >It is frustrating to have to use UNIX_TIMESTAMP(<date-time>,<format>) with UTC format string (plus that implementation uses SimpleDateFormat so the format string is much more restricted than DateTimeFormatter). >TO_TIMESTAMP and TO_TIMESTAMP_LTZ functions with String input with "by default, SQL or ISO formats are supported" would be valuable. some default ISO formats should be supported as support was added long time ago. For other topics: looks like it is not related to this PR so feel free either ask a question in ML or create a jira issue for this and submit a PR (if you think it could/should be improved) -- 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...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
