Querying Last Entries group by DeviceId

Posted by TTCG on Stack Overflow See other posts from Stack Overflow or by TTCG
Published on 2010-05-06T10:17:36Z Indexed on 2010/05/06 10:18 UTC
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mysql

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database

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distinct

I have the database table logs as the following:

alt text

I would like to extract the last entry of device, pollDate, status. For eg.

deviceId, pollDate, status

1, 2010-95-06 10:53:28, 1

3, 2010-95-06 10:26:28, 1

I tried to run the following query but the distinct only selects the first records, not the latest

SELECT DISTINCT deviceId, pollDate, status
FROM logs
GROUP By deviceId
ORDER BY pollDate DESC

alt text

So, could you please help me to extract the latest entries from the table? Thanks.

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