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WP Ajax Query allows you to query your WordPress database using the same query paramaters you would use for WP_Query, and return a JSON respresentation of the query results. This allows developers to easily interface with WordPress without having to relearn a new API.

How It Works

The Ajax Query interface would be available at http://example.com/wp-admin/admin-ajax.php?action=query

A sample jQuery request would be like:
$.get(ajaxurl, { action: ‘query’ }, function () { }, ‘json’);

Querying for a post:
$.get(ajaxurl, { action: ‘query’, p: 1 }, function () { }, ‘json’);

JSON results:
{
“id”: 1,
“type”: ‘post’,
“title”: “Hello World”,
“permalink”: “http:\/\/example.com\/?p=1”
}

Query a category:
$.get(ajaxurl, { action: ‘query’, cat: 1 }, function () { }, ‘json’);

JSON results:
{
“id”: 1
“type”: “category”,
“permalink”: “http:\/\/example.com\/?cat=1”,
“terms”: [],
“posts”: []
}

terms and `posts` represents an array of either terms that are sub categories of the category, or posts belonging to the category.<h3>Why I Created It</h3>

Needed a common way to query the database for posts and taxonomies across multiple plugins, and didn’t find a suitable replacement.

Details

Plugin code:
wp-ajax-query
Plugin version:
0.1
Outdated:
Yes
WP version:
3 or higher
PHP version:
or higher
Test up to WP version:
3
Total installations:
10
Last updated:
2010-05-27
Rating:
Times rated:
0
ajax
json
query
wp_query