Sql Query Locks

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 ...

The concept of blockchain to technology has been around for a long time, but with the heat of the past two years, it has gradually become known by the market and many technicians.

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 ...

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 ...

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 ...

Usually when we use the MySQL database, often because of operational errors caused by data loss, MySQL database backup can help us to avoid due to various reasons, data loss or other problems with the database. First, the data backup shortcut Because this method has not been the official official document validation, we tentatively called the experiment. Purpose: Backup hostA host a MySQL database backup TestA, and restored to the hostB machine in the test environment: Operating System: WinNT4.0, Mysql3.22.34, phpM ...

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 ...

The traditional relational database has good performance and stability, at the same time, the historical test, many excellent database precipitation, such as MySQL. However, with the explosive growth of data volume and the increasing number of data types, many traditional relational database extensions have erupted. NoSQL database has emerged. However, different from the previous use of many NoSQL have their own limitations, which also led to the difficult entry. Here we share with you Shanghai Yan Technology and Technology Director Yan Lan Bowen - how to build efficient MongoDB cluster ...

1: A simple introduction MongoDB is a distributed document database, supporting the master-slave structure of similar closed-type database, the document is stored in binary http://www.aliyun.com/zixun/aggregation/16702.html ">json form", No locks, no transactions, indexed. 2: Installation Steps Step one: Download the assembly http://www.mongodb.org/downloads Part II: Extract and extract the relevant bin directory to C ...

Type selection and design of bigtable NoSQL database release time: 2012.04.16 14:20 Source: Blog Author: Blog This paper introduces the selection strategy and schema design principle of Bigtable/hbase type NoSQL database system. Data scale BigTable Class database system (Hbase,cassandra, etc.) is to solve ...