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    <p>If you want to join automatically two rows that means that probably you can just create one row without spliting it:</p> <pre><code>file | date | face cyclist.jpg | 04-05-2012 | true </code></pre> <p>Otherwise if you need to keep separate rows, just select all rows in one query:</p> <pre><code>$res = mysql_query("select * from tags where file='cyclist.jpg'"); </code></pre> <p>and then iterate them to fulfil 'merged' record:</p> <pre><code>$res = mysql_query("select * from tags_table where file='cyclist.jpg'"); $mergedRow = array(); while ($row = mysql_fetch_assoc($res)) { foreach ($row as $rowKey =&gt; $rowValue) { if (!array_key_exists($rowKey, $mergedRow)) { $mergedRow[$rowKey] = $rowValue; } } } </code></pre> <p>Edit:</p> <p>As promised here's a sample of joining two rows into one with single query, however I would still recommend <code>$mergedRow</code> approach in PHP to merging them :)</p> <pre><code>CREATE TABLE `files_table` ( `id` int(11) unsigned NOT NULL AUTO_INCREMENT, `tag_type` enum('PARENT','CHILD') NOT NULL DEFAULT 'PARENT', `date` date DEFAULT NULL, `file` varchar(255) NOT NULL DEFAULT '', `face` smallint(4) NOT NULL DEFAULT '0', PRIMARY KEY (`id`) ) ENGINE=MyISAM AUTO_INCREMENT=1 DEFAULT CHARSET=utf8; </code></pre> <p>Then you can 'pair' PARENT-CHILDREN sets with:</p> <pre><code>SELECT t1.file, t1.date, t2.face FROM files_table AS t1 JOIN files_table AS t2 ON (t1.file = t2.file) WHERE t1.tag_type = 'PARENT' AND t2.tag_type = 'CHILD' GROUP BY file </code></pre>
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    1. COThanks biesior. At present I do it in code, but would like to select them all as one mysql result row. How can I create one result one with file | date | face as you first write?
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    2. CO@Sam: I showed you as it should be **stored** in DB, joining records from the same tables is not good idea, because you have almost no control on how values from conflicting columns will be merged, anyway I will write you a sample query soon.
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    3. COThe DB is structured as it is due to the semi-structured format of data. Some files have date information, some have face information, there are also about twenty other optional fields, which would be inefficient to have as columns in each row, as most files only have one or two tag types.
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