EdwardBock

Solr integration for your website. Replaces wordpress search query with solr apache core.
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Sunny Search

Solr integration for your website. Replaces wordpress search query with solr apache core.

mattweber

A WordPress plugin that replaces the default WordPress search with Solr. Features include:
<ul>
<li>Index pages and posts</li>
<li>Enable faceting on fields such as tags, categories, author, and page type.</li>
<li>Indexing and faceting on custom fields</li>
<li>Multisite support</li>
<li>Treat the category facet as a taxonomy</li>
<li>Add special template tags so you can create your own custom result pages to match your theme.</li>
<li>Completely replaces default WordPress search, just install and configure.</li>
<li>Completely integrated into default WordPress theme and search widget.</li>
<li>Configuration options allow you to select pages to ignore, features to enable/disable, and what type of result information you want output.</li>
<li>i18n Support</li>
<li>
Multi server/core support
Note that this plugin requires you to have an instance of Solr using a schema with the following fields: id, permalink, title, content, numcomments, categories, categoriessrch, tags, tagssrch, author, type, and text. The facet fields (categories, tags, author, and type) should be string fields. You can make tagssrch and categoriessrch of any type you want as they are used for general searching. The plugin is distributed with a Solr schema you can use at <code>solr-for-wordpress/schema.xml</code>.
</li>
</ul>
<h3>Credits</h3>
Dominique Bejean for custom field support and testing. 
Eric Pugh multi server support. 
Dustin Rue – fixes for batch import and multisite.

Solr for WordPress

A WordPress plugin that replaces the default WordPress search with Solr.

Sunny Search vs Solr for WordPress