BsoBird commented on code in PR #5891: URL: https://github.com/apache/hive/pull/5891#discussion_r2165497785
########## ql/src/java/org/apache/hadoop/hive/ql/udf/UDFUUIDV7.java: ########## @@ -0,0 +1,71 @@ +/* + * 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.hadoop.hive.ql.udf; + +import org.apache.hadoop.hive.ql.exec.Description; +import org.apache.hadoop.hive.ql.exec.UDF; +import org.apache.hadoop.io.Text; + +import java.util.UUID; +import java.util.concurrent.ThreadLocalRandom; + +/** + * UDFUUIDV7. + * + */ +@Description(name = "uuid_v7", + value = "_FUNC_() - Returns a universally unique identifier (UUID_V7) string.", + extended = """ + The value is returned as a canonical UUID 36-character string. + Example: + > SELECT _FUNC_(); + '0baf1f52-53df-487f-8292-99a03716b688' + > SELECT _FUNC_(); + '36718a53-84f5-45d6-8796-4f79983ad49d'""") +@UDFType(deterministic = false) +public class UDFUUIDV7 extends UDF { + private final Text result = new Text(); + /** + * Returns a universally unique identifier (UUID_V7) string (36 characters). + * + * @return Text + */ + public Text evaluate() { + result.set(randomUUIDV7().toString()); + return result; + } + + + private UUID randomUUIDV7() { Review Comment: @liach I'm sorry, sir, I apologize for underestimating the JVM's considerations for security. I now understand that there are valid reasons for using SecureRandom in the JVM. I just found that the efficiency of generating UUIDs with SecureRandom is really poor. UUIDv4 can still maintain a relatively decent production rate, while the current efficiency of UUIDv7 is far lower than that of UUIDv4. For a large data warehouse, using a UUIDv7 function with excessively low production efficiency may not meet the requirements at all. Therefore, I have chosen a relatively high-performance algorithm (although it does not fully comply with cryptographic security). If the performance of the JVM's built-in implementation is significantly improved in the future, I would prefer to use the JVM's built-in UUIDv7 algorithm. -- 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: gitbox-unsubscr...@hive.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: gitbox-unsubscr...@hive.apache.org For additional commands, e-mail: gitbox-h...@hive.apache.org
