References: <[EMAIL PROTECTED]> From: Scott Gifford <[EMAIL PROTECTED]> Date: 09 Apr 2002 15:40:38 -0400 In-Reply-To: [EMAIL PROTECTED]'s message of "Tue, 9 Apr 2002 21:28:35 +0200" Message-ID: <[EMAIL PROTECTED]> Lines: 33 User-Agent: Gnus/5.0807 (Gnus v5.8.7) Emacs/20.7 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii
[EMAIL PROTECTED] writes: > Your message cannot be posted because it appears to be either spam or > simply off topic to our filter. To bypass the filter you must include > one of the following words in your message: > > sql,query > > If you just reply to this message, and include the entire text of it in the > reply, your reply will go through. However, you should > first review the text of the message to make sure it has something to do > with MySQL. Just typing the word MySQL once will be sufficient, for example. > > You have written the following: > > Is there any reason to prefer a particular order of columns in the > table? > > For example, will SELECTs be faster if the columns are requested in > the same order they exist in the table? Is there a tendency for > columns earlier in the table to be preferred in queries with complex > WHERE clauses, so I should put columns which would be good candidates > for using their index earlier in the database? Is there any inherent > speed difference between earlier and later columns, for example > earlier columns are always at the beginning of the record, and so > won't require as much of the database file to be read to get their > value for each row? > > Thanks for any tuning tips along these lines; I'll do some benchmarks > tonight, but I was hoping somebody already knew this stuff and could > point me in the right direciton. > > ----ScottG. --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
