I've found a performance issue with a series of mysql queries that I make
to generate a web page. But, when I go to investigate it, reloading the
page a few times, I find the performance of the pages within a couple tries
becomes very fast.
So, it's hard to track down and work on the queries
At 11:35 AM 2/24/2004, Mike Johnson wrote:
It sounds like query caching is working against you.
There are a variety of ways to get around it. While it'll be a PITA, you
may want to have you script call `RESET QUERY CACHE` at the begining, and
then include `SQL_NO_CACHE` in your SELECT
At 12:07 PM 2/24/2004, Keith C. Ivey wrote:
Sounds like it's your operating system's caching of the disk reads.
Yikes... that would explain it.
um... anyone know how to disable disk caching on Linux 2.6 kernel?
-bill
--
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
I'm interested in trying to tune MySQL's memory usage variables in my
/etc/my.cnf file.
I'm currently using the default settings (except for max_allowed_packet,
which I've had to increase to support some large queries that I make), they
work well. Here is what I've got:
key_buffer_size
I am having problem using the operator OR. when I test for condition A
OR B in a query, the query becomes extensively slow or even fails,
even though a test on condition A or B alone gives result right away.
I learned recently that you can often use a UNION to solve problems like this.
It's
Looking around in the docs, I found this regarding thread_concurrency:
thread_concurrency
On Solaris, mysqld will call thr_setconcurrency() with this value.
thr_setconcurrency() permits the application to give the threads system a
hint for the desired number of threads that should be run at the
I've noticed that If I use an OR in my query, mysql seems to choose not to
use my indexes. Though, it would seem to help (as, if I do the query in
two steps, I can get faster results than as one query).
Is there some way I can convince mysql to use my keys with an OR, or
perhaps another way
At 01:54 PM 2/17/2004, walt wrote:
(SELECT FROM table WHERE condition1) UNION (SELECT FROM table WHERE
condition2);
Ah, interesting... I'll play around with UNION to see if that will do the
trick for me.
Right off the bat, I am able to get a fast query with it, but the output
isn't quite,
Is there a way to set PACK_KEYS=1 on existing tables without doing a dump
and load?
I didn't find it in the ALTER TABLE syntax.
--
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
I noticed these files in my mysql data directory:
-rw-rw1 mysqlmysql 5242880 Feb 15 20:54 ib_logfile0
-rw-rw1 mysqlmysql10485760 Feb 15 20:54 ibdata1
-rw-rw1 mysqlmysql 25088 Jun 3 2003 ib_arch_log_00
-rw-rw1 mysqlmysql
;
+-+
| UID |
+-+
| 255 |
+-+
1 row in set (0.11 sec
I've already worked around this, I'm just letting you guys know.
Fix:
Submitter-Id: submitter ID
Originator:Bill Marrs
Organization:
MySQL support: [none | licence | email support | extended email support ]
Synopsis: join
I don't have --no-disable-keys in my version of myqldump (Ver 8.21 Distrib
3.23.48). (-K doesn't seem to do anything, I assume it's the default).
I actually wouldn't mind disabling keys for the load, but I don't
understand how the /*!4 ... stuff is suppose to get used.
Is this a
In some recent release of MySQL, lines like this:
/*!4 ALTER TABLE States DISABLE KEYS */;
...were added to the output of mysqldump --opt.
This causes my usually load statement:
mysql dumpfile
...to fail with ERROR 1046 at line 11: No Database Selected.
If I do mydsql -f dumpfile it
I'm not an expert, but I've never heard of a db getting slower after an
index rebuild. It's possible that's just a red herring.
You've been speaking generally about things being slower, I'd suggest you
get specific. Track down the queries are slow now, use EXPLAIN on them to
see what
My code generates a large query. I had to increase the size of
max_allowed_packet so that this query would work.
I have this in my /etc/my.cnf file:
set-variable = max_allowed_packet=2097152
-bill
-
Before posting, please
Does anyone know of a Perl function or package that can take a
user-inputted string (like from a search form on web page) and turn it into
proper SQL.
Something that might be able to deal with quoting, parenthesis and use of
AND and OR. Perhaps also + and - syntax.
For example, if a user
At 03:53 PM 5/15/01 +0200, DEVOS BASTIEN wrote:
Excuse me but what do you mean by FullText ? Is this a full-text search
engine in MySQL ???
FULLTEXT is a kind of index in MySQL that allows for faster queries and
search-engine like relevance values for sorting the results.
Here's a link to some
At 02:59 PM 3/21/2001 +, soon chee keong wrote:
Table_1
-
A B C
-
1018 9
4 3 1
--
how can i change column C's "9" to say "20" without inserting a new record
and columns A and B remain
At 09:47 AM 3/20/2001 +0100, \"Piotr Gapinski\" wrote:
small problems with query below...
my fault?
mysql desc poll_answer;
+-+-+--+-+-+---+
| Field | Type|Null | Key | Default | Extra |
+-+-+--+-+-+---+
At 11:22 AM 3/20/2001 -0500, Ravi Raman wrote:
You can use an ENUM column type assuming the numerical range is less than
65535 numbers.
http://www.mysql.com/doc/E/N/ENUM.html
One problem I've seen with enums is that I end up with a blank ('') field
if I try to insert a row with a value in the
rror-check or update/delete all erroneous rows, or whatever you
decide to do.
...in other words, it's a feature, not a bug.
-ravi.
-Original Message-----
From: Bill Marrs [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, March 20, 2001 12:48 PM
To: [EMAIL PROTECTED]
Subject: RE: Second Request - Limit F
It is a known problem, I saw a bug report go through about it a day or so ago.
One workaround I found is to rename the key. I think the problem may have
something to do with the name of the key also being column name or a
special token.
In my case, I had:
int User,
key User(User)
and I
Hi,
I like to run mysqld with these 3 options:
--log-slow-queries
--delay-key-write-for-all-tables
--skip-networking
But, so far, I've been unable to get mysqld to read them out of /etc/my.cnf.
Here's what's inside my /etc/my.cnf:
[mysql.server]
log-slow-queries
delay-key-write-for-all-tables
At 01:23 PM 3/14/2001 +0100, Ren Tegel wrote:
you chowned mysql.cnf to owner/group mysql ?
I hadn't, but mysql is reading some other options properly from my
/etc/my.cnf file.
Actually, I did some more searching and I found this command:
/usr/libexec/mysqld --print-defaults
It seems to show
In the last episode (Mar 14), abdelhamid bettache said:
"In some circumstances it can be beneficial to split into two a
table that is scanned very often" I found these sentence in the mysql
manual , section 12.3:Get your Data as small as possible
Does every body know what are these
I've been running Redhat 7.0 for 5 months now on my production server,
haven't had any trouble with it.
I had trouble with the rpms for 3.23.34 that were on mysql.com's download page.
The server was getting intermittent signal 11's with blown stacks. I
assume a shared library mismatch.
My
I noticed that 'EXPLAIN TABLE' no longer shows the Privileges column, which
I think is a good thing as I'm never interested in it and it makes my
screen hard to read because it causes wrapping.
...but, mysqlshow still shows the Privileges column.
Is there any plan to make these two very
I'm not sure if anyone cares but... here's my final post on this topic.
I believe my signal 11 problem was due to me installing the 3.23.34 rpms
from mysql.com on top of my Redhat 7.0 system. I had heard that the RPMs
on mysql.com are Redhat 6.2 based and thus may be expecting different
At 05:14 PM 3/12/2001 +0200, Sinisa Milivojevic wrote:
Please try to make a repeatable test case if possible.
This means a set of commands that would always lead to MySQL crashing.
The problem does seem caused by a sequential set of operations. The script
that I've seen cause the problem
The problem does seem caused by a sequential set of operations. The script
oops, I'm meant to say "doesn't seem caused"
-bill
-
Before posting, please check:
http://www.mysql.com/manual.php (the manual)
FYI,
This problem got worse as more users began using the system. I had to
revert back to 3.23.28, which did solve the problem.
I'm sorry that I didn't come up with a reproducible test case. As near as
I could tell it seemed to be intermittent in nature. Things would work,
then not work.
31 matches
Mail list logo
