I want to compare every ID value at STATION3 to see if it matches the ID value at STATION2, if it matches, do something
That question makes sense if there were no {$row} in the middle; as is it is very unclear what you mean. How about some sample data, showing what is and isn't a match?

In reply to Re: Help me understand hashes by ysth
in thread Help me understand hashes by hallikpapa

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