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http://mysql-qotd.casperia.net/archives/268
mysql 5.0/5.1 questions for learning purposesFri, 06 Aug 2010 16:56:36 +0000http://wordpress.org/?v=abchourly1By: urs
http://mysql-qotd.casperia.net/archives/268/comment-page-1#comment-41
ursWed, 03 Mar 2010 16:00:55 +0000http://mysql-qotd.casperia.net/?p=268#comment-41<b>
Answers:
a c
Answer a is probably the most efficient.
b does not return the correct result.
d uses "MINUS", which is not supported in mysql.
The wgen table is filled with 10 rows. The insert selects from a cartesian join from 4 tables,
(well, 4 aliases of the same table) resulting in 10 * 10 * 10 * 10 = 10000 rows.
</b>
Answers:
a c
Answer a is probably the most efficient.
b does not return the correct result.
d uses “MINUS”, which is not supported in mysql.
The wgen table is filled with 10 rows. The insert selects from a cartesian join from 4 tables,
(well, 4 aliases of the same table) resulting in 10 * 10 * 10 * 10 = 10000 rows.