Mysql Force Index

MySQL database sql statement commonly used optimization methods 1. Query optimization, should try to avoid full table scan, should first consider where and order by the columns involved in the establishment of the index. 2. Should be avoided in the where clause on the field null value judgment, otherwise it will cause the engine to abandon the use of indexes and full table scan, such as: select id from t where num is null You can set the default value of num 0, to ensure that Num column table does not null value ...

Affirmation: The article is longer, if you are the industry webmaster please read carefully, welcome to join the industry webmaster QQ Group: 37466050 (using the invitation mechanism, add please specify the URL.) The rise of the industry web site has become an unstoppable trend in China's e-commerce development, according to a survey of 07 growth rate is expected to be close to 50%. For many industry websites, after a period of development, to seize the opportunity to win a certain market share. 　　At the same time, will face many new challenges, the market competition will become more and more fierce. Compared with the Internet companies that have VC support ...

CMS (Content Management system), translated into the Web site management systems, widely used abroad, is a fast web-building system core. In recent years, with the development of China's domestic internet, many corporate groups and individuals focused on the web industry have developed their own CMS, and many products have already matured. In the CMS system, there is free open source, there are commercial fees, and a variety of CMS also have their own characteristics, such as small and powerful tsys, K ...

When querying data, we often need to specify a few rows of data to be returned. As now there is a B/s architecture application, each page may display only 30 records. In order to improve the efficiency of the display, the database is generally required to return only 30 records at a time. When the user presses the next page, return 30 records from the database, and so on. This can shorten the time that the data is displayed. This is very effective when the base table for the query is larger. You can use the Limit keyword to implement this requirement at this time. The limit clause can be used to force a SELECT query statement to return ...

The advent of the 4G era, enterprise data faced with explosive growth, mobile TB; At the same time, human factors, software defects, uncontrollable natural disasters and other security problems occur frequently, how to make the enterprise data security and reliable, low-cost and efficient long-term preservation, has become an urgent concern for any enterprise. Fortunately, the cloud era accompanied by the 4G era, the core advantages of cloud computing: cost-effective, resource allocation, infrastructure flexibility, business smooth switching, bandwidth and storage unlimited expansion features. Multi-backup cloud backup, cloud recovery, cloud archiving and other special ...

Preface The construction of enterprise security building Open source SIEM platform, SIEM (security information and event management), as the name suggests is for security information and event management system, for most businesses is not cheap security system, this article combined with the author's experience describes how to use Open source software to build enterprise SIEM system, data depth analysis in the next chapter. The development of SIEM compared Gartner global SIEM rankings in 2009 and 2016, we can clearly see that ...

Note: This article starts in CSDN, reprint please indicate the source. "Editor's note" in this article for the online Office platform Gleasy co-founder, technical team boss Shike wrote, he gave us to share the gleasy all the way to the technical combat. It is reported that the release of nearly three years of Gleasy, has successfully accumulated more than 50,000 enterprise users, in response to mass storage and high concurrency under the premise of a variety of basic problems in the solution of deep experience. At the same time, March 18, 2015, Gleasy will officially release the 3.0 edition "about", and the introduction of English version, complex ...

Guide: Yahoo CTO raymie Stata is a key figure in leading a massive data analysis engine. IBM and Hadoop are focusing more on massive amounts of data, and massive amounts of data are subtly altering businesses and IT departments. An increasing number of large enterprise datasets and all the technologies needed to create them, including storage, networking, analytics, archiving, and retrieval, are considered massive data. This vast amount of information directly drives the development of storage, servers, and security. It also brings a series of problems to the IT department that must be addressed. Information...

The Battle of cloud Computing in the enterprise market has begun: new cloud service providers such as AWS have moved the cheese of traditional it giants in the corporate market, and traditional giants have struggled to fight back. With the advent of traditional it giants, PAAs markets have become more cluttered than ever before. 　　The only definite consensus seems to be one: everyone likes the word "platform/platform," because the word "platform" has unlimited imagination. More and more people are starting to talk and focus on PAAs, including operators, internet giants, traditional it vendors, consulting and integration ...