uuid

问题 When using a UUID data type as the primary key of a table, and asking H2 to generate each UUID value by default upon INSERT of a new record, how does one access the value of the newly generated UUID value? I am using plain JDBC 4.x in a Java app, if that helps with a solution. I know SCOPE_IDENTITY function returns a long for a key generated on a column marked as IDENTITY for an auto-incrementing sequence number. But I am using UUID rather than an incrementing number as my primary key column

问题 In a Java method that receives a java.util.UUID Object, I would like to display this object as a string in the .NET/C# format (CSUUID). Currently I am only able to display it in the Java format (JUUID) : static String GetStringFromUuid (java.util.UUID myUuid){ return myUuid.toString(); } Current output: "46c7220b-1f25-0118-f013-03bd2c22d6b8" Desired output: "1f250118-220b-46c7-b8d6-222cbd0313f0" Context: The UUID is stored in MongoDB and is retrieved with the Java ETL program Talend

问题 In a Java method that receives a java.util.UUID Object, I would like to display this object as a string in the .NET/C# format (CSUUID). Currently I am only able to display it in the Java format (JUUID) : static String GetStringFromUuid (java.util.UUID myUuid){ return myUuid.toString(); } Current output: "46c7220b-1f25-0118-f013-03bd2c22d6b8" Desired output: "1f250118-220b-46c7-b8d6-222cbd0313f0" Context: The UUID is stored in MongoDB and is retrieved with the Java ETL program Talend

问题 I have the following code written in Objective C that I am trying to get working in Swift 3. Some of the functions equivalents do not appear to be available in Swift 3. Here is the code is the code in Objective C NSUUID *vendorIdentifier = [[UIDevice currentDevice] identifierForVendor]; uuid_t uuid; [vendorIdentifier getUUIDBytes:uuid]; NSData *vendorData = [NSData dataWithBytes:uuid length:16]; and my current effort in Swift 3 which compiles and runs but is not giving the correct answer. let

问题 We have our app using uuids are primary keys, on a Postgresql Database. (Standard setup described here). We integrated ActiveStorage following the process described here. A standard setup using rails active_storage:install and migrated using rails db:migrate . We have a model & corresponding controller as follows: # Model class Message < ApplicationRecord has_one_attached :image def filename image&.attachment&.blob&.filename end end # Controller class MessagesController <

问题 Checked the cpython source code for both secrets and uuid4. Both seems to be using os.urandom. #uuid.py def uuid4(): """Generate a random UUID.""" return UUID(bytes=os.urandom(16), version=4) #secrets.py def token_bytes(nbytes=None): """Return a random byte string containing *nbytes* bytes. If *nbytes* is ``None`` or not supplied, a reasonable default is used. >>> token_bytes(16) #doctest:+SKIP b'\\xebr\\x17D*t\\xae\\xd4\\xe3S\\xb6\\xe2\\xebP1\\x8b' """ if nbytes is None: nbytes = DEFAULT

问题 Getting "Error: Package exports for 'D:\test\node_modules\uuid' do not define a '.' subpath" all the time when I require it. OS - Windows 10 Pro Node version - v13.1.0 NPM version - 6.14.4 I created a project from scratch and run npm init -y to create initial package.json Then I installed uuid by running npm install uuid and created index.js with nothing but only const { v4: uuidv4 } = require('uuid'); uuidv4(); from their example But whenever I try to run this code node ./index.js I always

问题 I'm needing to both validate a list of UUID's as well as determine the version. For example, using https://www.beautifyconverter.com/uuid-validator.php and entering 25CCCA6F-1568-473E-BFED-EC08C31532C6 I can determine that it is both valid, and version 4. I see from https://www.snip2code.com/Snippet/12614/Validating-a-uuid4-with-Python- and How to determine if a string is a valid v4 UUID? that the UUID module can validate one at a time, or test for a particular version, but not sure if UUID

问题 I don't understand why SELECT UUID(); Returns something like: 3f06af63-a93c-11e4-9797-00505690773f But if I insert it into a binary(16) field (the UUID() function) with for instance a BEFORE INSERT trigger and run a select, it returns something like: 0782ef48-a439-11 Note that these two UUIDs are not the same data. I realize binary and an UUID string doesn't look identical, but shouldn't the selected data at least be just as long? Otherwise how can it possibly be equally likely to be unique?

问题 I don't understand why SELECT UUID(); Returns something like: 3f06af63-a93c-11e4-9797-00505690773f But if I insert it into a binary(16) field (the UUID() function) with for instance a BEFORE INSERT trigger and run a select, it returns something like: 0782ef48-a439-11 Note that these two UUIDs are not the same data. I realize binary and an UUID string doesn't look identical, but shouldn't the selected data at least be just as long? Otherwise how can it possibly be equally likely to be unique?