Select multiple unique lines in MySQL

Posted by MartinW on Stack Overflow See other posts from Stack Overflow or by MartinW
Published on 2010-05-20T14:34:04Z Indexed on 2010/05/20 14:50 UTC
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sql

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mysql

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select

Hi,

I've got a table with the following columns:

ID, sysid, x, y, z, timereceived

ID is a unique number for each row.

sysid is an ID number for a specific device (about 100 different of these)

x, y and z is data received from the device. (totally random numbers)

timereceived is a timestamp for when the data was received.

I need a SQL query to show me the last inserted row for device a, device b, device c and so on.

I've been playing around with a lot of different Select statements, but never got anything that works. I manage to get unique rows by using group by, but the rest of the information is random (or at least it feels very random).

Anyone able to help me?

There could be hundreds of thousands records in this table.

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