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I have a layer of planning units covering a large area (there are over 16000 PU's). Three of the columns in the attribute table hold information about which planning units were included in the solutions from a conservation planning programme (Marxan). So the columns have an ID and then values ranging from 0 to 100 (the number of solutions that PU was included in).

What I am trying to do is to select the PU's from each column that were in all 100 solutions (so have a value of 100) - BUT only the PU's that match i.e. only PU's that have a value of 100 in ALL three columns (the columns represent different run scenarios).

I have tried SQL searches such as "ssoln_1 = 100 WHERE ssoln_2 = 100 AND ssoln_3 = 100" but my SQL is very basic and I am having no luck. Any suggestions would be hugely appreciated - I hope it all makes sense.

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1 Answer

It looks like you have the right idea. Make sure you have AND between each. Try:

ssoln_1 = 100 AND ssoln_2 = 100 AND ssoln_3 = 100

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But wouldn't that include PU's from, say, ssoln_1 that had a value of 100, even if that PU didn't get a score of 100 in the other two columns? I really need the PU's that score 100 in all three... –  Matt Aug 1 '12 at 20:43
    
The above command will only select features where all 3 attributes have the score 100. So that should work for your requirement. –  spatialthoughts Aug 2 '12 at 5:15
    
Excellent, it does work! - thanks for your help –  Matt Aug 2 '12 at 10:30
    
Great; glad to hear it Matt. If the answer worked for you, please upvote and mark click the checkmark to 'accept' the correct answer. –  Darren Cope Aug 2 '12 at 11:52
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