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POWriting a JOIN query with two counts from joined table
 

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    <p>I've spent a few hours fighting with this, but I can't get the counts to work. Hopefully someone can help?!</p> <p>I have a project table and task table, linked on the project_id. I can get the project_id, project_name, and the status_id with the query below:</p> <pre><code>SELECT a.project_id, a.project_name, b.status_id FROM project_list as a INNER JOIN task_list as b ON a.project_id=b.project_id </code></pre> <p>I'd like to select a single record for each project and add two count fields based on the status_id. In pseudo code:</p> <pre><code>SELECT a.project_id, a.project_name, (SELECT COUNT(*) FROM task_list WHERE status_id &lt; 3) as not_completed, (SELECT COUNT(*) FROM task_list WHERE status_id = 3) as completed FROM project_list as a INNER JOIN task_list as b ON a.project_id=b.project_id GROUP BY project_id </code></pre> <p>My create table scripts are below:</p> <pre><code>CREATE TABLE `project_list` ( `project_id` int(11) NOT NULL AUTO_INCREMENT, `topic_id` int(11) DEFAULT NULL, `project_name` varchar(45) DEFAULT NULL, PRIMARY KEY (`project_id`) ) CREATE TABLE `task_list` ( `task_id` int(11) NOT NULL AUTO_INCREMENT, `project_id` int(11) DEFAULT NULL, `task_name` varchar(45) DEFAULT NULL, `status_id` int(11) DEFAULT '0', PRIMARY KEY (`task_id`) ) </code></pre> <p>Any help is much appreciated. Thanks!</p> <p>EDIT: ANSWER:</p> <pre><code>SELECT a.project_id, project_name, SUM(status_id != 3) AS not_completed, SUM(status_id = 3) AS completed, SUM(status_id IS NOT NULL) as total FROM tasks.project_list as a INNER JOIN tasks.task_list as b ON a.project_id=b.project_id GROUP BY a.project_id </code></pre>
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