unity lock

There are two lock classification methods.(1) from the perspective of the Database SystemThere are three types of locks:• Exclusive Lock)A resource with an exclusive lock can only be used by locked programs. Other operations on the resource are not accepted. SQL Server automatically uses an exclusive lock when executin

MySQL Lab 1 .? MySQL concurrency and Isolation Control Mechanism Meta-data metadata lock: Implemented in the tablecache cache, provides isolation operations for DDL (DataDefinitionLanguage. A special meta-data metadata type called NameLock. (SQL layer) table-level data lock (SQL layer) storage engine-specific mechanism ro MySQL Lab 1 .? MySQL concurrency and Isolation Control Mechanism Meta-data metadata

Connect to the SQL server lock mechanism (I)-Overview (lock type and scope) Ii. Complete lock compatibility matrix (see) Correct Code Description: see. III. The following table lists the resources that can be locked by the database engine. Name Resources Abbreviations Encoding Specifies the method to describe the resource when a

Lock a table of a databaseSELECT * from table with (HOLDLOCK)Note: The difference between a table that locks a databaseSELECT * from table with (HOLDLOCK)Other transactions can read the table, but cannot update the deleteSELECT * from table with (TABLOCKX)Other transactions cannot read tables, updates, and deletesFeature description for "Lock options" in SELECT statementsSQL Server provides a powerful and c

[Unity skills] Optimization Technology in Unity and unity skills Optimization Technology Preface This article is based on a series of tutorials by Digital Tutors and summarizes the extended content ~ Digital Tutors is a great tutorial website. It contains many materials in the multimedia field and is very cool! In addition, we also refer to a tutorial in

One: Java multi-threaded mutex, and Java multithreading introduce the reason for the bias lock and lightweight lock? --->synchronized of the weight of the lock, that is, when the thread runs to the code block, the program's running level from the user state to the kernel state, to suspend all the threads, so that the CPU through the operating system instructions,

[Unity] Chapter 1 Unity Script Development basics, Chapter 2 unity Script Development Classification: Unity, C #, VS2015 Date created: 1. Introduction The attraction of a game lies in its interactivity. If the game has no interaction, the scenario will be more beautiful and exquisite, and it is difficult to call it a g

Tags: style io ar os using SP for data onOracle Lock table row-level lock table-level lock ----row is locked exclusively ----Other users cannot modify this line until a row's lock is released----use the commit or the rollback command to release the lock ----Oracle by using I

first line in C # will report an error (which is feasible in Java ). Initialization should be like this: String B = new string (new char [] {'A', 'B', 'C '});The answer is: 5 temporary objects Fifty-eight: what will happen to the following code during running? How to avoid it? List ls = new List (new int [] {1, 2, 3, 4, 5}); foreach (int item in ls) {Console. writeLine (item * item); ls. remove (item );}An error occurs during running. In the line ls. Remove (item), because foreach is read-only.

Tags: operation unique index nod implementation action hit principle BSP MySQL Lock process detailed (1)-Basics MySQL plus lock process details (2)-about MySQL read comprehension MySQL plus lock process details (3)-about MySQL read comprehension MySQL Lock process detailed (4)-select for Update/

First, Introduction Before we explain these lock concepts, we need to be clear that these locks are not equivalent to Reentratlock locks in the Java API, which are conceptually, the locking mechanisms that are created in JDK1.6 to optimize the synchronized synchronization keyword. The startup and shutdown policies for these locks can be set by setting the JVM startup parameters, and of course, in general, using the JVM default policy. second, Mark Wo

pessimistic lock, optimistic lock, only applicable to update operation In the actual production environment, if the concurrency is not small, can use pessimistic locking method, this method is very convenient and simple to use.However, if the concurrency of the system is very large, pessimistic locking can lead to very large performance problems, so choose optimistic locking method. Pessimistic locking ass