<pedrocorreia.net ⁄>
 

<How MySQL Uses Indexes ⁄ >




clicks: 2706 2706 2008-12-17 2008-12-17 goto programacao myNews programacao  Bookmark This Bookmark This


Indexes are used to find rows with specific column values quickly. Without an index, MySQL must begin with the first row and then read through the entire table to find the relevant rows. The larger the table, the more this costs. If the table has an index for the columns in question, MySQL can quickly determine the position to seek to in the middle of the data file without having to look at all the data. If a table has 1,000 rows, this is at least 100 times faster than reading sequentially. If you need to access most of the rows, it is faster to read sequentially, because this minimizes disk seeks.



este é só um excerto do artigo, para aceder ao artigo completo, clique no link em baixo:
this is just a small excerpt from the article, to access the full article please click in the link below:

http://dev.mysql.com/doc/refman/5.0/en/mysql-indexes.html




Subscribe News RSS  Subscribe News Updates by E-mail





myNews <myNews show="rand" cat="programacao" ⁄>

RouterJs: easy routing for your ajax Web applications new ...

RouterJs is a simple router for your ajax web apps. It's build upon History.js which means that Rout (...)

clicks: 15895 15895 2012-05-14 2012-05-14 goto url (new window) haithembelhaj.g... goto myNews programacao


Backbone computed properties new ...

This gist shows one way to implement read- and write-enabled computed properties on a Backbone Model (...)

clicks: 15719 15719 2012-05-13 2012-05-13 goto url (new window) https://gist.gi... goto myNews programacao


Android Query new ...

Android-Query (AQuery) is a light-weight library for doing asynchronous tasks and manipulating UI el (...)

clicks: 15946 15946 2012-05-12 2012-05-12 goto url (new window) code.google.com... goto myNews programacao


HTML5 jQuery Paint Plugin new ...

Websanova Paint is a HTML5 canvas based jQuery plugin. It allows you to free paint on a canvas area (...)

clicks: 26457 26457 2012-05-12 2012-05-12 goto url (new window) websanova.com/t... goto myNews programacao


Create Instagram Filters With PHP new ...

In this tutorial, I'll demonstrate how to create vintage (just like Instagram does) photos with PHP (...)

clicks: 15388 15388 2012-05-12 2012-05-12 goto url (new window) net.tutsplus.co... goto myNews programacao


Real-time Applications With Node.js and Socket.IO new ...

Hey everyone! Sorry about the long pause since the last blog post, life has been quite hectic for th (...)

clicks: 15787 15787 2012-05-11 2012-05-11 goto url (new window) codingcookies.c... goto myNews programacao


Sass vs. LESS vs. Stylus: Preprocessor Shootout new ...

CSS3 preprocessors are languages written for the sole purpose of adding cool, inventive features to (...)

clicks: 15112 15112 2012-05-11 2012-05-11 goto url (new window) net.tutsplus.co... goto myNews programacao


Gettings to know Backbone.ks new ...

In this series, we're going to learn how to build a fully functional contacts manager using Backbone (...)

clicks: 14738 14738 2012-05-10 2012-05-10 goto url (new window) net.tutsplus.co... goto myNews programacao