Comments on: Question 41: Which of the queries is the most efficient? http://mysql-qotd.casperia.net/archives/305 mysql 5.0/5.1 questions for learning purposes Fri, 06 Aug 2010 16:56:36 +0000 http://wordpress.org/?v=abc hourly 1 By: urs http://mysql-qotd.casperia.net/archives/305/comment-page-1#comment-47 urs Tue, 09 Mar 2010 19:51:52 +0000 http://mysql-qotd.casperia.net/?p=305#comment-47 <b>   Answer:   b   b reads the table only once - a and c read it 3 times to get the result.   </b>
 
Answer:
 
b
 
b reads the table only once – a and c read it 3 times to get the result.
 

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