Profile Sql Query

It is well known that query optimization is an unavoidable topic in any database. For database engineers, optimization is the most challenging job. MySQL Open source database is no exception. In fact, the author believes that the database optimization is not as much as we imagine the suffering. 　　Under normal circumstances, you can start from the following four details to do a good job in the MySQL database query optimization. First, use the Explain keyword to evaluate the flaw in the query statement as shown in the following figure, now the author in the database to execute a simple select ...

Intermediary transaction http://www.aliyun.com/zixun/aggregation/6858.html ">seo diagnose Taobao guest cloud host technology Hall in the consideration of a website if the host million or tens of millions of PV, We tend to think in two directions instinctively: static and distributed. Of course, for Sina and other portal types of Web sites, static + read and write separation and distribution, can solve most of the problems. But we are facing more, may be large data + high and ...

In the development of friends especially and MySQL have contact friends will encounter sometimes MySQL query is very slow, of course, I refer to the large amount of data millions level, not dozens of, the following we take a look at the resolution of the query slow way. -Often find developers looking up statements that are not indexed or limit n, which can have a significant impact on the database, such as a large table of tens of millions of records to scan all, or do filesort, and the database and server IO impact. This is the case above the mirrored library. And ...

Big data has grown rapidly in all walks of life, and many organizations have been forced to look for new and creative ways to manage and control such a large amount of data, not only to manage and control data, but to analyze and tap the value to facilitate business development. Looking at big data, there have been a lot of disruptive technologies in the past few years, such as Hadoop, Mongdb, Spark, Impala, etc., and understanding these cutting-edge technologies will also help you better grasp the trend of large data development. It is true that in order to understand something, one must first understand the person concerned with the thing. So, ...

Big data has grown rapidly in all walks of life, and many organizations have been forced to look for new and creative ways to manage and control such a large amount of data, not only to manage and control data, but to analyze and tap the value to facilitate business development. Looking at big data, there have been a lot of disruptive technologies in the past few years, such as Hadoop, Mongdb, Spark, Impala, etc., and understanding these cutting-edge technologies will also help you better grasp the trend of large data development. It is true that in order to understand something, one must first understand the person concerned with the thing. So, ...

Top Ten Open Source technologies: Apache HBase: This large data management platform is built on Google's powerful bigtable management engine. As a database with open source, Java coding, and distributed multiple advantages, HBase was originally designed for the Hadoop platform, and this powerful data management tool is also used by Facebook to manage the vast data of the messaging platform. Apache Storm: A distributed real-time computing system for processing high-speed, large data streams. Storm for Apache Had ...

The concept of large data, for domestic enterprises may be slightly unfamiliar, the mainland is currently engaged in this area of small enterprises. But in foreign countries, big data is seen by technology companies as another big business opportunity after cloud computing, with a large number of well-known companies, including Microsoft, Google, Amazon and Microsoft, that have nuggets in the market. In addition, many start-ups are also starting to join the big-data gold rush, an area that has become a real Red sea. In this paper, the author of the world today in the large data field of the most powerful enterprises, some of them are computers or the Internet field of the Giants, there are ...

This series of articles is a learning record about the fundamentals of azure services development, and because of time constraints, the process of wishing to discuss and explore yourself is from scratch, to be able to develop basic programming for azure services. There may be a very deep topic relative to each topic, and I would like to have time to do it through other articles. 　　The positioning of this series is basically positioning, take 20-30 minutes, download the code first, follow the article, run to get the relevant experience. The previous article is about Azure queue storage, this is about ...

Intermediary trading http://www.aliyun.com/zixun/aggregation/6858.html ">seo diagnose Taobao guest cloud host technology Hall April 18, 2009, I, A5 security group of the light son, Morning received the call. A user said the site's web site is not normal access. Is it black? There are some problems with the website users. 　　User profile is very anxious. I opened the user's website. Found it was indeed inaccessible. The page is blank. ...

"Editor's note" The Black Hat Convention's scale is increasing year in, this is the world's smartest brain together, will wipe out what kind of lightning Flint, this year's Black Hat Congress attracted nearly million people to participate in, these technical men are very consistent with the "Matrix" in the "Keanu" image standards, eyes deep, stand upright, poor speech, It is said that there are many FBI site recruitment, in short, attracted the global vision. This article has counted the cool 10 tools of this Conference, and it is worth to be happy that most of them are open source. 2014 Black Hat Convention display hacker tool can help penetration tester Discover VoIP pass ...