how to lock ssn

TAGS: SQ negative LSE a high concurrent Har direct CAL schemeExamples of items to buy:① Gets the quantity of inventory from the database.② Check if the quantity of stock is sufficient.The quantity of ③ inventory minus the amount purchased by the buyer (in the case of each user buying one).④ final purchase completed.Just a few lines of logical code in the case of concurrency will be problematic, you can imagine.It is not tested here for the time being, and the following will give the test results

Examples of items to buy:① Gets the quantity of inventory from the database.② Check if the quantity of stock is sufficient.The quantity of ③ inventory minus the amount purchased by the buyer (in the case of each user buying one).④ final purchase completed.Just a few lines of logical code in the case of concurrency will be problematic, you can imagine.It is not tested here for the time being, and the following will give the test results for concurrent processing.To create a table:CREATE TABLE ' W

Examples of items to buy:① Gets the quantity of inventory from the database.② Check if the quantity of stock is sufficient.The quantity of ③ inventory minus the amount purchased by the buyer (in the case of each user buying one).④ final purchase completed.Just a few lines of logical code in the case of concurrency will be problematic, you can imagine.It is not tested here for the time being, and the following will give the test results for concurrent processing.To create a table:CREATE TABLE ' w

Lock (Locking)In the process of implementing business logic, it is often necessary to guarantee the exclusivity of data access. such as in the final settlement of the financial systemProcessing, we want to process the data for a cut-off point in time, and we don't want to be in the process of closing(may be a few seconds, or maybe a few hours), and the data will change again. At this point, we need to pass some machineSystem to ensure that this data i

Relationship between innodb table level lock and lock table statement, innodbtable DDL statements only apply for intention-Level Table locks. In the lock table statement, mysql applies for mysql-Level table locks, and innodb also applies for innodb-Level table locks. The premise is that innodb_table_locks = 1 Https://www.percona.com/blog/2012/07/31/innodb-table

I recently read Java Concurrent in Practice (java Concurrent programming Practice) and found that I have a superficial understanding of java threads, locks, and other mechanisms, and I have not learned fully enough. I plan to use this book to comprehensively learn about the concurrent development of JDK and some thread-related theoretical knowledge, and fill in my own gaps. I can also communicate with you and understand what is incorrect, thank you for your correction. In the first blog, I will

Lock Lock IntroductionJDK1.5 Previously, we implemented thread synchronization by means of the synchroized keyword or block locking to ensure that operations within the scope of the keyword are atomic operations.After JDK1.5, the concurrency package provided is more powerful and more flexible, and the most critical is the need to manually release the lock, which

A while ago, we introduced some of the new features of Windows 8.1, which are one of the more appealing changes that can be automatically replaced by a lock screen as if it were a desktop wallpaper. In fact, to experience it does not have to wait for win 8.1 release, with a small tool, can immediately let your win 8 change 8.1. The software, named Lock Screen Customizer, is a dedicated Win8 enhancement sof

In Reentrantlock, it is obvious that there are two kinds of synchronization, namely, fair fairsync and unfair Nonfairsync. The function of the fair lock is strictly according to the sequence of the thread start, do not allow other threads to jump in line execution, and the unfair lock is allowed to queue. By default, Reentrantlock is synchronized through an unfair lock