https://www.simple-talk.com/sql/t-sql-programming/row-versioning-concurrency-in-sql-server/?utm_source=tuicool&utm_medium=referral Concurrency(Locking, Blocking and Row Versioning)…

Like ever, today’s article of Pinal Dave was interesting and informative. After, our mutual discussion between our DBAs and Developers on Pinal Dave topic of Concurrency and Isolation. I felt that most of us are intermingling three equally sounding w…

This is a by-design behavior. There is only one allocation unit in tempdb that istracking the versioned records across the server. Cleanup of this allocationunit is decided by the oldest transaction of READ_COMMITTED_SNAPSHOT enableddatabase.  SQL Se…

Github上的1000多本免费电子书重磅来袭!   以前 StackOverFlow 也给出了一个免费电子书列表,现在在Github上可以看到时刻保持更新的列表了. 瞥一眼下面的书籍分类目录,你就能知道这个免费电子书库的含金量了吧.记得一定要看几本,千万别下载了大量书籍而束之高阁! 行动重于空想! Github地址:     https://github.com/vhf/free-programming-books/blob/master/free-programming-books.md I…

Index Ada Agda Alef Android APL Arduino ASP.NET MVC Assembly Language Non-X86 AutoHotkey Autotools Awk Bash Basic BETA C C# C++ Chapel Cilk Clojure COBOL CoffeeScript ColdFusion Cool Coq D Dart DB2 Delphi / Pascal DTrace Elasticsearch Emacs Erlang F#…

http://www.dadbm.com/database-hang-row-cache-lock-concurrency-troubleshooting/ Issue backgroundThis post will help to analyze Oracle database instance slowdown that can happen due to considerable row cache lock (enqueue) wait events. It’s is based on…

大家好,欢迎回到性能调优培训.今天标志着第5个月培训的开始,这个月我们会谈论SQL Server里的锁.阻塞和死锁(Locking, Blocking, and Deadlocking). SQL Server提供悲观和乐观并发控制模式,它们用来定义并发查询的执行.这期我会给你讲解悲观并发控制模式里各种隔离级别概况,下周我会进一步介绍自SQL Server 2005起引入的乐观隔离级别情况. 悲观隔离级别(Pessimistic Isolation Levels) 悲观隔离级别意味着读查询(SE…

大家好,欢迎回到性能调优培训.上个星期我通过讨论悲观并发模式拉开了第5个月培训的序幕.今天我们继续,讨论下乐观并发模式(Optimistic Concurrency). 行版本(Row Versioning) 乐观并发模式自SQL Server 2005后引入,并基于行版本控制(Row Versioning)原则.行版本控制背后的想法是读操作(SELECT查询)不再需要获得共享锁(Shared Lock).不去等待直到成功获得共享锁(Shared Lock),读操作是返回行前一个提交的版本.老的…

14.3 InnoDB Transaction Model and Locking 14.3.1 InnoDB Lock Modes 14.3.2 InnoDB Record, Gap, and Next-Key Locks 14.3.3 Avoiding the Phantom Problem Using Next-Key Locking 14.3.4 Consistent Nonlocking Reads 14.3.5 Locking Reads (SELECT ... FOR UPDATE…

我们监控SQL SERVER数据库的阻塞情况时,老是收到在SSRS 里面出现SQL阻塞情况,刚开始由于事情多,没有太关注ReportServerTempDB里面的会话阻塞情况,但是老是出现这种频繁阻塞情况,不得不仔细研究一下SSRS的Blocking问题.   Blocking SQL Text CREATE PROCEDURE [dbo].[Writelocksession] @SessionID        AS VARCHAR(32),                          …