Hi,
Ok, I'm out of ideas. The additional index should have sped things up,
not
slowed them down. I've got some tables with 26,000 rows in it and I do 4
joins (using a WHERE clause) with smaller tables without a hitch.
Sorry I can't help.
But thanks a lot for trying. :) And thanks also to
Hi everyone,
I'm stuck on one issue which is preventing me from using MySQL in production
on one particular database. (This is similar to my last post but this time
I'll explain better what I'm attempting to do.)
I'm trying to create a database of filenames and directories using MySQL. I
have
A .03 sec left join PREVENTS you from using MySQL.
This must be a troll.
You have no where clause, so no index is used.
Jordan Russell wrote:
Hi everyone,
I'm stuck on one issue which is preventing me from using MySQL in production
on one particular database. (This is similar to my last
A .03 sec left join PREVENTS you from using MySQL.
This must be a troll.
Sigh...
I guess I failed to mention this was a deliberately simplified example in
order to pose my question in a easy-to-understand manner. In reality, there
are much more records, and a more complex query, where the
You have no where clause, so no index is used.
Oops, missed this part.
Where exactly do I need a WHERE clause, and for what? The first query
doesn't have a WHERE clause and yet it appears to be using the "date" index.
Jordan Russell
Hi,
Thanks for the reply.
Hve you read
http://www.mysql.com/documentation/mysql/bychapter/manual_Performance.html#L
EFT_JOIN_optimization
?
Yes, many times, as well as just about everything else in the Performance
chapter. Am I missing something totally obvious? Should I even be using a
LEFT
were your results?
Cal
http://www.calevans.com
-Original Message-
From: Jordan Russell [mailto:[EMAIL PROTECTED]]
Sent: Monday, March 12, 2001 2:27 PM
To: Cal Evans
Cc: [EMAIL PROTECTED]
Subject: Re: Need help optimizing this (simple) query
Hi,
Thanks for the reply.
Hve you read
http
Everything I've seen on this list indicates that using LEFT JOIN negates
using an index. (WARNING: This is 3rd hand info and as such should be
viewed
skeptically!)
Have you tried:
SELECT files.id, dirs.name FROM files where files.dir_id=dirs.id
ORDER BY files.date DESC LIMIT 1;
If so,
(dir_id),
to the above.
Cal
http://www.calevans.com
-Original Message-
From: Jordan Russell [mailto:[EMAIL PROTECTED]]
Sent: Monday, March 12, 2001 2:48 PM
To: Cal Evans
Cc: [EMAIL PROTECTED]
Subject: Re: Need help optimizing this (simple) query
Everything I've seen on this list indicates
Jordan Russell wrote:
Everything I've seen on this list indicates that using LEFT JOIN negates
using an index. (WARNING: This is 3rd hand info and as such should be
viewed
skeptically!)
Have you tried:
SELECT files.id, dirs.name FROM files where files.dir_id=dirs.id
ORDER BY
/* This table has 5000 rows */
CREATE TABLE files (
id int(11) NOT NULL auto_increment,
dir_id int(11) NOT NULL default '0',
name varchar(100) NOT NULL default '',
date datetime default NULL,
PRIMARY KEY (id),
KEY date (date)
) TYPE=MyISAM;
for grins and giggles, add:
key
Message-
From: Jordan Russell [mailto:[EMAIL PROTECTED]]
Sent: Monday, March 12, 2001 3:07 PM
To: Steve Ruby
Cc: Cal Evans; [EMAIL PROTECTED]
Subject: Re: Need help optimizing this (simple) query
Do you have an index on files that starts with dir_id and
an index on dirs that stats with id
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