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Getting Rows from a MySQL Table with max values?

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Top Forums Programming Getting Rows from a MySQL Table with max values?
# 8  
Old 05-04-2012
Quote:
Originally Posted by Corona688
It has to be something that, theoretically, can be done in a single pass.

It can find the highest value easily enough it needn't print anything until it's over. But to find all rows that match the highest value in one pass, it would need to be psychic -- it has to scan the entire table to figure out what the highest is. Once it's done that it's already printed all the results and can't start over.

Indexes and the like make searching and min/max a lot faster than brute-force table scans now, but they aren't used to make the database 'psychic' this way, because that'd mean inconsistent behavior.
So when I do the "having" clause it returns the first value on the list because it only scans the first element and then reads in this first value as being max -so "done"

Well, I guess code is code. If it works it doesn't have to be readable. Smilie
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