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    <p>We can use a SELECT statement with a GROUP BY school to create a record for each school. The ties, wins, and losses columns are readily calculated with the SUM aggregate function, as you noted. To target a specific round, we can use some clever math (to avoid verbose conditional statements like the one CodeByMoonlight suggested):</p> <p>If we want to target round R, we note that "round-R" is 0 only when round == R, otherwise it isn't 0. When we take the NOT of "round-R", 0 gets inverted to 1, while everything else gets set to 0. Now, if we multiply !(round-R) by the score of that round, it will give us 0 when the round is not R (as 0*score = 0) and it will give us "score" when the round is R (as 1*score = score). Next, when we take the SUM of this value over the columns, we add score when round=R and 0 otherwise, effectively giving us just the round R score. </p> <p>Putting that all together gives:</p> <pre><code>SELECT school AS `School`, SUM(!(round-1)*score) AS `Round1`, SUM(!(round-2)*score) AS `Round2`, SUM(!(round-3)*score) AS `Round3`, SUM(!(round-4)*score) AS `Round4`, SUM(!(round-5)*score) AS `Round5`, SUM(!(round-6)*score) AS `Round6`, SUM(!(round-7)*score) AS `Round7`, SUM(!(round-8)*score) AS `Round8`, SUM(!(round-9)*score) AS `Round9`, SUM(!(round-10)*score) AS `Round10`, SUM(win) AS `wins`, SUM(loss) AS `losses`, SUM(tie) AS `ties` FROM `RoundScores` GROUP BY `school` </code></pre> <p>where RoundScores is the table in question.</p> <p>EDIT:</p> <p>If we do not want to manually add 10, we can use <a href="http://dev.mysql.com/tech-resources/articles/4.1/prepared-statements.html" rel="nofollow">prepared statements</a> :</p> <pre><code># Store all the conditionals in a string: # I was not able to to have round loop from 1 to 10, so I iterated over # all distinct values of 'round' present in the table. SET @s = ""; SELECT `round`, (@s := CONCAT( @s , "SUM(!(round-",round, ")*score) AS `Round",round, "`," )) FROM `RoundScores` GROUP BY `round`; # Combine the conditionals from before with the rest of the statement needed. SET @qry = CONCAT("SELECT school AS `School`,",@s,"SUM(win) AS `wins`,SUM(loss) AS `losses` FROM `RoundScores` GROUP BY `school`"); # Prepare and execute the statement. PREPARE stmt1 FROM @qry; EXECUTE stmt1; </code></pre>
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