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http://mysql-qotd.casperia.net/archives/198
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/198/comment-page-1#comment-26
ursTue, 16 Feb 2010 18:08:58 +0000http://mysql-qotd.casperia.net/?p=198#comment-26<b>
Answers:
a b
The gender doesn't have a lot of distinct values, so an index on it will not restrict the data very much. Indexing a sum is probably not a good idea either, as usually you want to report sums but not select by them. A date field is probably a good candidate for an index, as processing by date is a common task. Also indexing a user-id sounds like a good idea.
</b>
Answers:
a b
The gender doesn’t have a lot of distinct values, so an index on it will not restrict the data very much. Indexing a sum is probably not a good idea either, as usually you want to report sums but not select by them. A date field is probably a good candidate for an index, as processing by date is a common task. Also indexing a user-id sounds like a good idea.