Optimistic locking problem

Is there the concept of optimistic locking in TP5.1? I don't see it mentioned in the manual.

*ptr 2019-04-13 16:14:11 0  0  1314

PHP - The choice between pessimistic locking and optimistic locking under high concurrency

Tell me what you think and please correct me if I am wrong. The implementation principle of optimistic locking is cas operation, and lightweight locks in Java are also implemented based on cas. The biggest problem with pessimistic locking is blocking. In an in-depth understanding of the Java virtual...

ringa_lee 2017-05-16 13:05:01 0  4  966

mysql - Since innodb has gap locks at the RR isolation level, why do two transactions still produce deadlocks due to different locking orders? ?

Deadlock is caused by multiple transactions competing for the same resource. Whether it is two SQL statements in two transactions, the locking order of the resources being operated is different, or the locking order of the resources operated by one SQL statement in the two transactions is different....

ringa_lee 2017-05-18 10:54:38 0  1  835

php - What is the role of memcache locking?

{code...}

曾经蜡笔没有小新 2017-05-16 13:00:31 0  1  396

php - How to ensure data security when one operation requests multiple services?

An order operation to purchase goods. To simultaneously reduce user points, insert an order. In the same library, pessimistic locking can be added to the points table to prevent concurrently generated data from being read multiple times. Now that HTTP is used to request points service and order serv...

我想大声告诉你 2017-05-25 15:08:18 0  3  965

java - Why can the get() method in ConcurrentHashMap not be locked?

{Code...} Why does Vector’s get need to use synchronized for locking but ConcurrentHashMap does not? Moreover, CopyOnWriteArrayList also uses copy-on-write to achieve parallel reading and writing, but obviously ConcrrentHashMap does not implement copy-on-write. How does it maintain...

漂亮男人 2017-05-17 10:00:31 0  1  973

node.js - How does nodejs crawler control the number of requests?

When using nodejs to crawl web page content, if there are too many requests, sometimes an exception will be thrown, prompting errors such as too many connections. Does nodejs have such keywords or libraries for thread locking? Or how to handle it better? First, thank you!

滿天的星座 2017-06-27 09:19:30 0  2  1181

Implement lock mechanism using PHPRedis

I got the following two functions for locking Redis keys. I'm trying to prevent concurrent execution of blocks of code using Redis. So what I did was use the following function to prevent different threads from executing the same code. lockRedisKey("ABC");CODETHATIDON'TWANTTORUNCONCURRENTL...

P粉515066518 2023-08-28 18:33:09 0  2  796

Laravel cache lock already locked?

TLDR: How to check if a Laravel atomic lock is locked without locking it and checking the return value of the $lock->get() call? I have multiple Laravel commands executed through the scheduler. A command is not scheduled and if it is running, no other commands should be run. So I introduced atomi...

P粉818561682 2024-03-27 13:28:19 0  1  670

linux - How to understand mutex locks and condition variables?

The following code is from "Unix/Linux Programming Practice Tutorial". Its function is to use two threads to count the number of words in two files respectively, and calculate the total number in the main thread. The following is a running screenshot: But after watching it for a long time,...

仅有的幸福 2017-06-12 09:24:46 0  1  1365

Laravel Modal does not return data

I don't know why I'm not getting the value from the modal in my Laravel controller. Please check it for me. However, I use the same code for other modes and controllers. It's working and returning the value from the property without any issues. I'm using Laravel8 and php8.1; below is my code. app\Ht...

P粉174151913 2024-03-29 10:31:31 0  1  661

Can I use the automatic generation module of thinkphp5 in Windows 7 system? How to configure and use

明民 2017-10-10 17:04:14 0  2  1452

After installing the PHP toolbox, all the mysql tables in phpstudy that I installed before are gone. What should I do?

After installing the PHP toolbox, all the mysql tables in phpstudy that I installed before are gone. What should I do?

刘袁铭 2017-10-10 19:25:59 0  4  3008

mcrypt_get_key_size()

To use mcrypt_get_key_size() in php study, how to enable mcrypt_

刘袁铭 2017-10-10 19:47:34 0  1  1231

Detecting login status and preventing repeated login status in TP5 - My page is wrong

冥冥之中天注定 2017-10-10 22:49:15 0  0  1252

Issues with resending WeChat public account template messages?

For example: I am using PHP to develop WeChat public accounts. If I send a template message, the WeChat client may receive 1-3 messages. I checked Baidu and said that the WeChat server will resend in 5 seconds. How to solve this problem?

飞扬 2017-10-11 08:00:11 0  0  1164

How to install php7

我无限黑暗里的小太阳▼ 2017-10-11 09:11:44 0  1  1167

Solve (no language limit)

A census taker asked a woman, "How many children do you have and how old are they?" The woman replied, "I have three children. Their ages multiplied is 36. The sum of their ages is equal to the house number of the segregated room." Census The enumerator immediately went to the ne...

路过 2017-10-11 10:20:08 0  1  1406

There is no WWW file in the phpStudy directory. Enter localhost in the website and the hello world solution will come out directly! I created the WWW folder in the root directory and then created an abc.php. localhost/abc.php still didn't come out and an error was reported. not found

<?phpphpinfo();?>

M..moli瞎 2017-10-11 11:45:27 0  7  5247

Find an authoritative and practical development tutorial or article on WeChat scan code authorization to log in to the website

Find an authoritative and practical development tutorial or article on WeChat scan code authorization to log in to the website

极世 2017-10-11 12:33:15 0  1  1722