News Feed
Sections




News Archive
Looking for more information on how to do PHP the right way? Check out PHP: The Right Way

Andrei Zmievski's Blog:
Bloom Filters Quickie
April 07, 2009 @ 11:13:01

Andrei Zmievski has written a new post about a new extension he's worked up (out of curiosity for the technology) - the pecl/bloomy extension.

A Bloom filter is a probabilistic data structure that can be used to answer a simple question, is the given element a member of a set? Now, this question can be answered via other means, such as hash table or binary search trees. But the thing about Bloom filters is that they are incredibly space-efficient when the number of potential elements in the set is large.

The filters allow false positives with a defined error rate - it gives the "yes" or "no" answer based on the content and you, the developer, decide if that answer falls within a rate that's okay for you and your app. The filters also take the same amount of time to look up items no matter how many are in the set.

He includes an example of the extension in use - defining the number of elements, the false positive allowance and adding/searching data and how the responses would come back from the checks.

0 comments voice your opinion now!
bloom filter pecl extension example false positive rate data structure


blog comments powered by Disqus

Similar Posts

SitePoint PHP Blog: How to Handle Unloaded PHP Extensions at Runtime

Smashing Magazine: Cleaning Up The Mess: How To Keep Your Coding Workflow Organized

Richard Davey\'s Blog: Prepare for PHP 6

Lukas Smith\'s Blog: MDB2 example

Devollo.com: Data Filtering Using PHP's Filter Functions - Part one


Community Events

Don't see your event here?
Let us know!


wordpress voicesoftheelephpant series community library opinion podcast unittest development introduction framework extension api laravel5 interview threedevsandamaybe release language laravel feature

All content copyright, 2015 PHPDeveloper.org :: info@phpdeveloper.org - Powered by the Solar PHP Framework