kiosk lock

Lock, lock 1. view the current Lock ObjectSelect a. owner,A. object_name,B. xidusn,B. xidslot,B. xidsqn,B. session_id,B. oracle_username,B. OS _user_name,B. process,B. locked_mode,C. machine,C. status,C. server,C. sid,C. serial #,C. programFrom all_objects,V $ locked_object B,V $ session cWhere (a. object_id = B. object_id)And (B. process = c. process)Order by 1,

operated like our mobile phone. You only need to press and hold it with the left mouse button, and then gently drag it up to enter the login interface or desktop. So, is there any skill that can make us better play with the screen lock? Quick screen lock tips: Use the shortcut key Win + L to quickly lock the frequency. Press Ctrl + Alt + Del and select "

1. Object lock key Only one can be mutually exclusive, in order to guarantee the uniqueness of shared variables2. In the static method of the lock, and the instance method on the lock, the default is not the same, if the synchronization needs to make two locks.3. The lock on a method of the same class comes from the ob

Why do I need a lock (concurrency control)?In a multiuser environment, multiple users may update the same record at the same time, which can create a conflict. This is the famous concurrency problem.Typical conflicts are:L Lost Update: One transaction update overwrites the update result of other transactions, that is, the so-called update is lost. For example: User A changes the value from 6 to 2, and User B changes the value from 2 to 6, then user a

1.FLUSH TABLES with READ LOCKThis command is a global read lock, and all of the library tables are locked for read-only after the command has been executed. is generally used in the database online backup, this time the database write operations will be blocked, read operation smoothly.The unlocked statement is also unlock tables.2.LOCK TABLES tbl_name [as alias] {READ [LOCAL] | [Low_priority] WRITE}This co

I. Introduction 1.1 process/Thread Synchronization Method Common process/Thread Synchronization Methods include Mutex, rdlock, cond, and Semophore. In windows, the Critical Section and Event are also common Synchronization Methods. 1.2 recursive lock/non-recursive lock Mutex can be divided into recursive mutex and non-recursive mutex ). Recursive locks are also called reentrant mutex. non-recursive locks ar

In the process of implementing business logic, it is often necessary to guarantee the exclusivity of data access. Therefore, we need some mechanism to ensure that the data will not be modified by the outside in the course of operation, such a mechanism, in this case, the so-called "lock", that is, to our selected target data locked, so that it can not be modified by other programs.Hibernate supports two types of locking mechanisms:1. Pessimistic

/** * @author Admin * @date 2018/1/12 9:48 * Function on the same instance object to discuss * synchronized Synchronous method Test * Two threads, one thread calls synchronized adornment method, another thread can call non s Ynchronized modified method, non-impact */public class Synchronizedtest {public synchronized void MethodA () {try {fo R (int i = 0; i /** * @author Admin * @date 2018/1/12 10:16 * Function on the same instance object to discuss * sychronized code block Test

A. Lock can be used instead of the Synchronized keyword to implement the mutex function. Use the following methods: Lock L = ...; L.lock (); try { //access the resource protected by this lock } finally { l.unlock (); } It is to be noted that. 1. One or more methods that require mutual exclusion use the same mutex. 2. In th

Tags: Insert query exist UPD HTML IMA drop info LANMysql Series Articles Home===============1 Preparing data1.1 Build Table1.1.1 Establishment of employee tablesDROP TABLE IF EXISTS employee; CREATE TABLE IF not EXISTS Employee ( INTPRIMARYKEY auto_increment, VARCHAR(+), INT) engine MyISAM;1.1.2 Build Department TableDROP TABLE IF EXISTS Department; CREATE TABLE IF not EXISTS Department ( INTPRIMARYKEY auto_increment, VARCHAR (+)) engine MyISAM;1.1.3 Note: The storage engin

Another mechanism for implementing thread synchronization or mutual exclusion in Java 5 is the use of lock. Lock is more object-oriented than the synchronized method in the traditional threading model.Mutual-exclusion lock –lock (Reentrantlock)A mutex is a lock that can be h

Unable to obtain the lock/var/lib/dpkg/lock-open (11: temporary resource unavailable) solve the problem: an error occurs when the program is updated: unable to obtain the lock/var/lib/dpkg/lock-open (11: temporary resource unavailable) solution: in fact, this is because another program is running, resulting in... unabl

Pessimistic lock (pessimistic lock), as the name implies, is very pessimistic, every time to take the data when they think others will change, so every time when the data are locked, so that others want to take this data will block until it gets the lock. Traditional relational database in the use of a lot of this locking mechanism, such as row locks, table locks

1, pessimistic lock, as its name, it refers to the data by the outside (including the system's current other transactions, as well as the transaction from the external system) is conservative attitude, so throughout the process of data processing in the lock state. Pessimistic lock implementation, often rely on the database provided by the

　　Pessimistic lock (pessimistic lock), as the name implies, is very pessimistic, every time to take the data when they think others will change, so every time when the data are locked, so that others want to take this data will block until it gets the lock. Traditional relational database in the use of a lot of this locking mechanism, such as row locks, table loc

A minute teaches you to know the difference between optimistic and pessimistic locks Category: Database2014-07-08 14:06 17588 people read reviews (2) favorite Report Pessimistic lock (pessimistic lock), as the name implies, is very pessimistic, every time to take the data when they think others will change, so every time when the data are locked, so that others want to take this data will block until it get

Optimistic lock and pessimistic lock in Java;1. Java is a typical synchronized is a pessimistic lock, that is, exclusive lock, but JDK1.6 after the synchronized has done a lot of optimization, can not be said to be completely pessimistic lock;2. Optimistic locking is a kind

Redis implements pessimistic locks.Principle, in the grab lock, Rob failed to wait a second to rob, and then another second to rob, so repeated circulation.Unlocking means deleting the corresponding key./** * Realize Redis pessimistic lock * User:babytuo*/ClassRedislock { Public $expire= 2; Public functionTest () {$this->lock ("Test1"); Echo"111"; } Public f

In Ubuntu, there are times when you use sudo apt-get install to install software. E:could not get Lock/var/lib/dpkg/lock-open (11:resource temporarily unavailable)E:unable to lock-administration directory (/var/lib/dpkg/), is another process using it? At this time, mainly because apt is still running, at this point the solution is 1, find and kill all the Apt-g

1. Samsung mobile phone Almost all the features of the setup is from the "application" started, we click on the desktop application to enter.2. Then click the "Set" button in the Application management interface to enter.3. Go to the Setup Panel and find the "Device" tab click on it.4. Then we are in the set to the "Lock screen" menu, as shown in the Figure red box below.5. After entering, we click on "screen lock