Mysql On Duplicate Update

1, use the index to traverse the table faster. The index created by default is a non-clustered index, but sometimes it is not optimal. Under non-clustered indexes, the data is physically stored on the data page. Reasonable index design should be based on the analysis and prediction of various inquiries. In general: a. There are a large number of duplicate values, and often range query (>, <,> =, <=) and order by, group by occurred columns, consider the establishment of cluster index; Column, and each column contains duplicate values ​​can be ...

1, use the index to traverse the table faster. The index created by default is a non-clustered index, but sometimes it is not optimal. Under non-clustered indexes, the data is physically stored on the data page. Reasonable index design should be based on the analysis and prediction of various inquiries. In general: a. A large number of duplicate values, and often range query (>, <,> =, <=) and order by, group by occurred column, consider the establishment of cluster index; b. Column, ...

The intermediary transaction SEO diagnoses Taobao guest Cloud host technology Hall A5 source code, provides the massive free website source code to the user to download! March also has a large number of excellent source code in the functional aspects or performance updates to optimize, same as ever, this month for you to organize some of the source code specific updates details. 　　Hope to be helpful to the friends who want to learn to do the website or the user who is using. The online editor 162100editor (HTML editor) is a mini HTML editor, only one JS file is buttoned up. Its characteristic is: code ...

Intermediary trading SEO diagnostic Taobao customer hosting technology hall this month A5 source code mainly for the following categories sorted out the latest source code dynamic: enterprise website system, community forums, blog space, CMS system, school classes, shop, mall system, E-commerce, etc., I hope you are using the help. Enterprise website ETS corporate website system is based on a PHP + Mysql architecture website content management system, but also a PHP development platform. Modular way to develop, easy to use features easy to expand, can be ...

The complete collection of SQL statement operations deserves to be permanently stored the following statements are part of the MSSQL statement and are not available in Access. SQL classification: ddl-data Definition language (create,alter,drop,declare) dml-Data Manipulation Language (Select,delete,update,insert) dcl-Data Control Language (Grant,revoke, Commit,rollback first, briefly introduce the basic statement: 1, Description: Create number ...

Baigostudio posted on: March 25, 2015-------------------v1.1.1-------------------2015-03-25 allows each page to be set to show the number of 2015-03-20 Improve the background interface password update JS, reduce password error probability baigovalidator upgrade to v0.1.0 2015-03-19 repair article data model, the installation is missing a table ...

Intermediary transaction SEO diagnosis Taobao guest Cloud host technology Hall O2O is not a simple offline transfer, but a complete service chain two weeks hungry? By the public comment on investment 80 million U.S. dollars, valued 500 million, spread to 300 employees, each is million elder sister, million elder brother. 　　This kind of situation, very rare, the American WhatsApp happened this kind of thing, China this is the first. Some people think this is the concept of speculation, some people think that this is the capital of the game, there are people who feel hungry is simply a blow out ...

Intermediary transaction SEO diagnosis Taobao guest Cloud host Technology Hall 1, what is the directory submission? Everyone is familiar with the phone or directory Yellow pages. They contain a list of people or sorts of businesses in alphabetical order or by category. 　　Internet directories are basically the same, but they are known as web directories or online catalogs, and they are by category sites. In order for your site to be listed on these pages, you must first submit to the directory. If you do not submit your site directory differently, users will not be able to find your site unless they know what is due to an accident or input ...

1. Languages used in COUCHDB: Erlang features: DB consistency, easy to use license: Apache protocol: http/rest bidirectional data replication, continuous or temporary processing, processing with conflict checking, therefore, The use of Master-master replication (see note 2) mvcc– write without blocking read operation Pre-save version crash-only (reliable) design requires data compression view: Embedded mapping/Reduce formatted view: List display support for server ...