read lock

This article mainly introduces the MySQL row-level lock, table-level lock, page-level lock detailed introduction, while enumerating some examples, the need for friends can refer to the followingPage level: Engine BDB.Table level: Engine MyISAM,

the basic principle of lockIn order to ensure the data is finished and consistent, the database system adopts the lock to realize the isolation of the transaction. The basic theory of locks used in various large databases is consistent, but there

Core points of Knowledge:1. Table and row-level locks represent the level of lock, and read and write locks represent the true type of lock.2. Read locks are shared locks, share the same resource, do not interfere with each other; write locks are

This article mainly introduces the MySQL row-level lock, table-level lock, page-level lock detailed introduction, while enumerating some examples, the need for friends can refer to the followingPage level: Engine BDB.Table level: Engine MyISAM,

Welcome to the Linux community forum and interact with 2 million technical staff. In order to better optimize mysql in high concurrency situations, it is necessary to understand the lock table mechanism when mysql queries updates. I. Overview MySQL

MySQL row-level lock, table-level lock, page-level lock details page-level: engine BDB. Table-level: engine MyISAM, which is interpreted as locking the entire table and reading at the same time. Row-level: engine INNODB, locking a single row of

Source of this article: www.lustlost.com? P101mysql supports logical backup and physical backup Based on backup and recovery methods. Logical backup is a backup SQL statement, and the number of databases is achieved by executing the backup SQL

Page Level: Engine BDB.Table-level: Engine MyISAM, which is interpreted as locking the entire table and reading at the same time.Row-level: Engine INNODB, locking a single row of records At the table level, the entire table is locked directly.

A deep understanding of oracle transaction isolationIn Oracle relational database, let's look at the following question:A transaction: select from T where id> 10 and id Transaction B: update T set id = 45000 where id = 4501The two transactions are

How to lock a MySQL database table There are mainly a variety of methods to prevent client requests from interfering with each other or mutual interference between servers and maintenance programs. If you close the database, you can ensure that

Mysql backup and recovery bitsCN.com Mysql backup classification:Mysql data backup:Logical backup and physical backupMysql is classified by dataset:Full BackupIncremental BackupDifferential backupThese types are generally used in combination. for

In the isolation level of the transaction, it is possible to understand the impact of data that can occur when two different transactions are occurring concurrently. Careful words can be found in the Transaction isolation level section, Dirty read ,

In multithreaded programming, shared variables need to be locked. However, frequent locking can have a significant effect on program efficiency. In some scenarios where read and write less, it is clearly not necessary for multiple threads to read

Function Description: Manipulate file characteristics According to the file description.#include #include int fcntl (int fd, int cmd);int fcntl (int fd, int cmd, long arg);int fcntl (int fd, int cmd, struct flock *lock);DescriptionFCNTL () provides

MySQL lock mechanism details and deadlock Handling Methods To optimize MySQL in high concurrency, it is necessary to understand the lock table mechanism when MySQL queries an update. I. OverviewMySQL has three levels of locks: Page, table, and

The Lock Tables command locks the table for the current thread. Here are 2 types of locks, one is read lock, with command lock tables TableName read, another is write lock, with command lock tables tablename Write. The following are described

Transferred from: http://www.cnblogs.com/lonelycatcher/archive/2011/12/22/2297349.htmlFunction Description: Manipulate file characteristics According to the file description.#include #include int fcntl (int fd, int cmd);int fcntl (int fd, int cmd,

Pessimistic lock and optimistic 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

This article is based on the Dbaplus community on the 104th issue of the online sharing.Original: http://dbaplus.cn/news-11-1267-1.htmlInstructor IntroductionFeng YuPoint-and-melt Network Advanced DBA Oracle OCM, MySQL OCP; Currently

The MyISAM engine is a non-transactional engine that provides high-speed storage and retrieval, as well as full-text search capabilities, and is suitable for applications where queries are frequently used in data warehouses. In MyISAM, a table is