Joe Kaiping writes:
Is it expected that using the LOWER function should greatly increase query
time?
The way you do it, yes.
Is that email column a BLOB or a BINARY VARCHAR? If not,
why on earth do you do LOWER() on it? And do you have an
index on the column?
//C
--
Carl Troein - CĂrdan
Hi there,
Is it expected that using the LOWER function should greatly increase query
time? Or is there a MySQL setting that can help speed it up? Below are the
results of a query against a table that has an index on cols (email,cust).
Using LOWER increases the query time by 10.5 seconds.
To: [EMAIL PROTECTED]
Subject: why would LOWER
Hi there,
Is it expected that using the LOWER function should greatly increase query
time? Or is there a MySQL setting that can help speed it up?
Below are the
results of a query against a table that has an index on cols (email,cust).
Using
was wondering if something like that may be happening.
Thanks for the comments!
-Joe
-Original Message-
From: Will French [mailto:[EMAIL PROTECTED]]
Sent: Sunday, September 30, 2001 1:25 PM
To: [EMAIL PROTECTED]; [EMAIL PROTECTED]
Subject: RE: why would LOWER
You didn't mention how large
Hi.
The problem is that LOWER(email) is an expression and expressions on
the left hand side of an comparison cannot use an index with MySQL
(see also http://www.mysql.com/doc/M/y/MySQL_indexes.html).
If you usually want to compare emails ignoring case, an easier way is
to assure that email is
]
Subject: RE: why would LOWER
You didn't mention how large your table is or if the email
and cust fields
are part of an index.
In many situations, the results you are seeing make perfect
sense to me. If
email is a part of an index then the LOWER function may need
to be performed
Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Benjamin
Pflugmann
Sent: Sunday, September 30, 2001 1:55 PM
To: Joe Kaiping
Cc: [EMAIL PROTECTED]
Subject: Re: why would LOWER
Hi.
The problem is that LOWER(email) is an expression and expressions on
the left hand
MySQL is not Oracle ... and that's a good thing, too! :-)
Tom Haapanen
[EMAIL PROTECTED]
-Original Message-
From: Joe Kaiping [mailto:[EMAIL PROTECTED]]
Sent: 30 September 2001 19:37
To: [EMAIL PROTECTED]
Subject: RE: why would LOWER
Thanks to all for your responses. I had missed