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Exclude the Two Highest Outliers from Query

Posted on 2007-03-21
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Last Modified: 2012-05-05
The query at http:Q_22463410.html will exclude the row with an outlier (the 1 highest number) in a particular column, like this:

$sql = 'SELECT ID, Student, Score FROM scores t1 WHERE t1.Student = "Doe" AND t1.Score != (SELECT MAX(Score) FROM scores t2 WHERE t2.Student="Doe") ORDER BY Score ASC';

Is it possible to exclude the *two* rows with the highest numbers?  For example, if the scores in that column are:  500, 499, 100, 99, 100, 98, 97, 95, I would need the query to exclude both the 500 and the 499.  (I don't want to use any arbitrary cutoffs, because the numbers will vary greatly depending on the target.)
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Question by:Randall-B
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6 Comments
 
LVL 143

Assisted Solution

by:Guy Hengel [angelIII / a3]
Guy Hengel [angelIII / a3] earned 1000 total points
ID: 18765922
$sql = 'SELECT ID, Student, Score FROM scores t1 WHERE t1.Student = "Doe" AND t1.Score NOT IN (SELECT Score FROM scores t2 WHERE t2.Student="Doe" ORDER BY score DESC LIMIT 2) ORDER BY Score ASC';
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Author Comment

by:Randall-B
ID: 18766036
angelIII,
   Thanks. But I'm getting an error:
     "This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery' "
   I'm using the latest version of WAMP. I think it's a 4.xx version of MySQL.  Is there any way around this limitation?  
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LVL 143

Expert Comment

by:Guy Hengel [angelIII / a3]
ID: 18766088
no, unless you create temporary table with the subquery result
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Author Comment

by:Randall-B
ID: 18766162
OK. Then please explain how to create and use a temporary table in this situation. Thanks.
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LVL 143

Accepted Solution

by:
Guy Hengel [angelIII / a3] earned 1000 total points
ID: 18766196
query1:
CREATE TABLE tmp_StudentScore
SELECT Score FROM scores t2 WHERE t2.Student="Doe" ORDER BY score DESC LIMIT 2

query2:
SELECT ID, Student, Score FROM scores t1 WHERE t1.Student = "Doe" AND t1.Score NOT IN (select Score from tmp_StudentScore ) ORDER BY Score ASC

query3:
DROP TABLE tmp_StudentScore

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Author Comment

by:Randall-B
ID: 18766351
That works for me.  Thanks so much.
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