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    <p>Stuart's answer shows you how to get the sum of the column, but I just want to note that:</p> <pre><code>...WHERE drivers LIKE '%jill%'... </code></pre> <p>will return any event with a driver whose name contains the letters 'jill'.</p> <p>Secondly, this database design doesn't seem to be normalized. You have driver names and route names repeated. If you normalize the database and have something like:</p> <p><b>participant</b></p> <pre> id | name | role </pre> <p><b>event</b></p> <pre> id | date | route_id | description | executed </pre> <p><b>route</b></p> <pre> id | name | distance </pre> <p><b>participant_event</b></p> <pre> id | participant_id | event_id </pre> <p>then it would be a lot easier to work with the data.</p> <p>Then if you wanted to implement a user search, you could make the query:</p> <pre><code>SELECT id FROM participant WHERE name LIKE '%jill%' AND role='driver'; </code></pre> <p>Then if the query returns more than one result, let the user/application choose the correct driver <i>and then</i> run a <code>SELECT SUM</code> like Stuart's query:</p> <pre><code>SELECT SUM(r.distance) FROM route r JOIN event e ON e.route_id=r.id JOIN participant_event pe ON e.id=pe.event_id JOIN participant p ON pe.participant_id=p.id WHERE p.id=?; </code></pre> <p>Otherwise, the only way to ensure that you're only getting the total distance driven by <b>one</b> driver is to do something like this (assuming <code>drivers</code> is comma-delimited):</p> <pre><code>...WHERE LCASE(drivers)='jill' OR drivers LIKE 'jill, %' OR drivers LIKE '%, jill' OR drivers LIKE '%, jill,%'; </code></pre>
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    1. POHow to get the sum of a column from combined tables in mySQL?
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    1. CODidn't think about %jill% problem, thanks for noticing! The site is a very small private service with a tiny database, that's why I didn't think about normalization or optimizing querys and such (and it was quite a while since I took the database class). However, I will definitely redesign the database and make it normalized, there is really no excuse for not doing it right.
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    2. COYea, I just thought I'd throw it out there. I mean, sometimes a normalized db isn't the most optimal design. But for this particular search, it does kill 2 birds with one stone by also making it easier to pull data on a specific driver.
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