Modify MySQL INSERT statement to omit the insertion of certain rows

Posted by dave on Stack Overflow See other posts from Stack Overflow or by dave
Published on 2011-01-17T02:29:48Z Indexed on 2011/01/17 2:53 UTC
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I'm trying to expand a little on a statement that I received help with last week. As you can see, I'm setting up a temporary table and inserting rows of student data from a recently administered test for a few dozen schools. When the rows are inserted, they are sorted by the score (totpct_stu, high to low) and the row_number is added, with 1 representing the highest score, etc.

I've learned that there were some problems at school #9999 in SMITH's class (every student made a perfect score and they were the only students in the district to do so). So, I do not want to import SMITH's class.

As you can see, I DELETED SMITH's class, but this messed up the row numbering for the remainder of student at the school (e.g., high score row_number is now 20, not 1).

How can I modify the INSERT statement so as to not insert this class?

Thanks!

DROP TEMPORARY TABLE IF EXISTS avgpct ;
CREATE TEMPORARY TABLE avgpct_1
   ( sch_code    VARCHAR(3),
     schabbrev   VARCHAR(75),
     teachername VARCHAR(75),
     totpct_stu  DECIMAL(5,1),
     row_number  SMALLINT,
     dummy       VARCHAR(75)
   );
-- ----------------------------------------
INSERT INTO avgpct
SELECT sch_code
     , schabbrev
     , teachername
     , totpct_stu
     , @num := IF( @GROUP = schabbrev, @num + 1, 1 ) AS row_number
     , @GROUP := schabbrev AS dummy
  FROM sci_rpt
 WHERE grade = '05' AND 
       totpct_stu >= 1   -- has a valid score
 ORDER 
    BY sch_code, totpct_stu DESC ;
-- ---------------------------------------
-- select * from avgpct ;
-- ---------------------------------------
DELETE 
  FROM avgpct_1
 WHERE sch_code = '9999' AND 
       teachername = 'SMITH' ;

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