Oracle Database Locks

As a software developer or DBA, one of the essential tasks is to deal with databases, such as MS SQL Server, MySQL, Oracle, PostgreSQL, MongoDB, and so on. As we all know, MySQL is currently the most widely used and the best free open source database, in addition, there are some you do not know or useless but excellent open source database, such as PostgreSQL, MongoDB, HBase, Cassandra, Couchba ...

The scalability of the system is the main reason for promoting the development of NoSQL movement, including distributed system coordination, failover, resource management and many other features. That makes NoSQL sound like a big basket that can be stuffed with anything. Although the NoSQL movement does not bring fundamental technological changes to distributed data processing, it still leads to extensive research and practice on protocols and algorithms. It is through these attempts to gradually summarize some effective database construction methods. In this article, I will focus on the NoSQL database distributed special ...

The scalability of the system is the main reason for promoting the development of NoSQL movement, including distributed system coordination, failover, resource management and many other features. That makes NoSQL sound like a big basket that can be stuffed with anything. Although the NoSQL movement does not bring fundamental technological changes to distributed data processing, it still leads to extensive research and practice on protocols and algorithms. It is through these attempts to gradually summarize some effective database construction methods. In this article, I will focus on the distributed features of the NoSQL database ...

As two of the most popular technologies in the field of information management, the hardware architecture of database integration machine and large data technology is basically the same, but the software system has the essential difference, which leads to the different characteristic performance. With the rapid growth of enterprise data and the continuous improvement of users ' requirements for service level, the traditional relational database technology has shown obvious lack of ability in production practice for a long time. How to obtain high availability of massive data at reasonable cost has become a major challenge in modern it field. In order to meet this challenge, in recent years, it market ...

Today's IT World, database NoSQL and newsql processing data way, has gone beyond the use of traditional relational databases. Traditional relational databases don't disappear forever--but their brilliance has passed. Many of the NoSQL databases that have just come out have become popular, such as Mongndb and Cassandra. This is a good remedy for the limitations of the traditional database system. Of course, relative to the rapid development of NoSQL, the database system based on SQL is rather lifeless. This should be the database needs constant Progress update ...

NoSQL systems generally advertise a feature that is good performance and then why? relational database has developed for so many years, various optimization work has been done very deep, nosql system is generally absorbing relational database technology, and then, in the end what is the constraints on the performance of relational database? We look at this problem from the perspective of http://www.aliyun.com/zixun/aggregation/9344.html "> System design." 1, index support. Relational data ...

November 2013 22-23rd, as the only large-scale industry event dedicated to the sharing of Hadoop technology and applications, the 2013 Hadoop China Technology Summit (Chinese Hadoop Summit 2013) was held at four points by Sheraton Beijing Group Hotel. 　　Nearly thousands of CIOs, CTO, architects, IT managers, consultants, engineers, enthusiasts for Hadoop technology, and it vendors and technologists engaged in Hadoop research and promotion will be involved in a range of industries from home and abroad. In S ...

A few days, in the management of the system encountered a strange problem, today have the opportunity to install the MySQL environment to reproduce the problem, because it is not the most primitive environment, so may not be able to fully reproduce, I can only try to reproduce the key The problem .. I think this issue is a bit special, so in this probably recall the scene under the circumstances .. Work, the implementation of a su & ndash; mysql command, encountered such an error .. view sourceprint? 1 [root @dbmain ~ ...

This paper is an excerpt from the book "The Authoritative Guide to Hadoop", published by Tsinghua University Press, which is the author of Tom White, the School of Data Science and engineering, East China Normal University. This book begins with the origins of Hadoop, and integrates theory and practice to introduce Hadoop as an ideal tool for high-performance processing of massive datasets. The book consists of 16 chapters, 3 appendices, covering topics including: Haddoop;mapreduce;hadoop Distributed file system; Hadoop I/O, MapReduce application Open ...

Intermediary transaction SEO diagnosis Taobao Guest Cloud mainframe technology hall with the advent of the 11 long holiday, everyone to the Ministry of Railways 12306 of the discussion again. This article (original) from 12306 website extension to the site performance of a lot of discussion, for entrepreneurs and technology enthusiasts have a strong reference. 　　The author Chenhao (Weibo) has 14 years of experience in software development, 8 years of project and team management experience. 12306.cn website Hung, was scolded by the people all over the country. I've been here for two days.