Ummm... You know you can GROUP BY multiple fields, right? 
SELECT stop_reference, service_id, min(distance)
FROM table
GROUP BY stop_reference, service_id ;

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The basic rule is that you can include as many fields in a summary query as you like, provided that each one of them has either a summary operation (such as min()) or a GROUP BY applied to it. (This does rule out anything like SELECT * without going to a subquery, but, then, I only use SELECT * when I'm querying by hand anyhow. Using it in my code carries too much risk of breakage if the table's columns get reordered.)

In reply to Re^2: Help with manipulating data from a database?? by dsheroh
in thread Help with manipulating data from a database?? by Harch84

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