Slow Query Log

Slow Query
i have this query on a website/webapp that has expanded beyond all expectation. It now takes nearly 30secs to return results from the database

SELECT cl_t.Client_ID, Buyer_1_Title, Buyer_1_Prename,
Buyer_1_Surname, Tel_No, Mob_No, Buyer_2_Title,
Buyer_2_Prename, Buyer_2_Surname, Email_Add,
Price_Max, MAX(activity_t.Date) AS lastcomm
FROM cl_t
INNER JOIN cl_want_t
ON cl_t.Client_ID = cl_want_t.Client_ID
AND Agency_Code ='$agencyloggedincode'
AND Deleted = 'N'
LEFT JOIN activity_t
ON Buy_Sell = 'B'
AND Ref_No = cl_t.Client_ID
WHERE cl_t.Sales_Agent_ID = $agentid
GROUP BY cl_t.Client_ID
ORDER BY $order
The problem is the call to MAX(activity_t.Date) AS lastcomm

activity_t holds all known contact with all known clients and as such is a very large table, the call to search through all of these records and return only the date of the last entry for this client is taking the time. If I remove this from the query I get results in 3 seconds.

I have indexing on activity_t.Date & activity_t.Ref_No

Question, is there a way of doing this quicker within the table I already have, or should I create another table that just holds the last update date for each client, and get the date from this much smaller table.

---

Why Is This Query Too Slow?
I find this query to be exceptionally slow(around 2.5 seconds), could some tell me why this is so?

MySQL
SELECT st.profile_views,count( DISTINCT p.ID ) news_submitted, count( DISTINCT pv.ID ) news_voted, count( DISTINCT pcom.ID ) news_commented, u.joined, u.weight FROM users u LEFT JOIN posts p ON p.submitted_user_id = u.user_id LEFT JOIN post_votes pv ON pv.user_id = u.user_id LEFT JOIN post_comments pcom ON pcom.user_id = u.user_id LEFT JOIN stats st ON st.user_id=u.user_id WHERE u.user_id='john' GROUP BY u.user_id
I traced the cause to this line
count( DISTINCT p.ID ) news_submitted (from LEFT JOIN posts p ON p.submitted_user_id=u.user_id)
But when i execute something like this

MySQL
SELECT count( DISTINCT p.ID ) news_submitted FROM posts WHERE submitted_user_id='john'
it is quite fast (around 0.03 seconds)
So why does it slow down when i'm joining the above query with 3 other tables ?
Should i use INTEGER for user_id instead of string like 'john'?

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Slow Query Using NOT IN
I am migrating a MSSQL server to MySQL. I know the following SQL is valid for both servers, but MSSQL finishes execution of the query almost instantly, and MySQL has been running the query for the past ten minutes and still is not finished. There is basically the same amount of data in each database. Does anyone know ....

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Slow Query
I have a query that is running really slow !!!!
I have joined on Key fields and indexed the tables fully but it is still solw.
--------------------------------------------

select d.id, a.signed, u.Forename, u.Surname, d.paid, p.date, d.payment, p.amount, d.acctual
from details d
join poten a
on a.id = d.id
left join recieved p
on d.id = p.id
left join users u
on a.signed = u.userid
where d.paid > '01-Dec-2005'
and d.authorrceived is not null
and d.authorrefused is null
and ((d.payment starting 'E' or
d.payment starting 'e') or
(d.payment starting 'Q' or
d.payment starting 'q' and
p.target = '500'))
order by d.paid, a.signed, d.id

---

Slow Update Query
I have about 2000 update queries to do, which takes about 1 hr on 250,000 rows.
My table is getting kinda slow here is the query i am using
UPDATE nametable SET
sectionname = replace(sectionname,'".$oldsec."','".$sec."'),
categoryname = replace(categoryname,'".$oldcat."','".$cat."'), published=Ƈ'
where sectionname='".$oldsec."'
and categoryname='".$oldcat."' ;

I am wondering if the same thing is possible with an insert... on duplicate key statement?

I cant seem to get the insert statement to work, but not even sure whether it is appropriate.

With this query I am basically finding and replacing some columns based upon another table (within the php script I am using)

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Slow Query Log Files
I have edited my.ini file to create a file called slow queries. My problem is that when the server starts up i do not get a full list of all slow queries. Is there anything else i need to change? How else can i come about in getting all queries that took a long time to execute? im using mySQL 5.0.9.

---

Slow Query Log Not Staying On
I'm running MySQL 4.0.16 on Windows 2003. I just added the mysqld-nt
command line option to enable the slow query log, started MySQL, and the
option showed up as turned on. Then later I restarted the server, and the
slow query log option went back to being turned off. Is this a Windows
problem in not remembering the service parameter? Has anyone else seen
this?

---

View Slow Query Log
I searched here, google and MySQL docs but did not find an answer.
I'm using MySQL-Front from a Windows platform to administer a remote database. The remote server doesn't have phpMyAdmin or anything like that.
MySQL-Front reports 133 Slow Queries and an average of 15 queries per second. But I dont' know how get more information than that.

---

Query With 3.3million Rows Is Slow?
I'm not that great with MySQL...so I was hoping someone could help me out.
The query I'm running is too slow...can anyone tell me what I can do to
speed it up..if I can at all? I was wondering if because ZipListMatrix has
3.3 million rows that 8 seconds is all the faster it's going to be. Any
help is greatly appreciated! I have already "optimized" the tables.

---

Can't Turn On Slow Query Logging
long_query_time = 1
log-slow-queries = /var/lib/mysql/slow_queries.log
Is the above syntax not correct for enabling slow query logging? All examples I've seen have the dashes in the second variable and underscores in the first.

When I restart MySQL with those lines in my.cnf, it fails to start, but writes nothing to its error log.
/var/lib/mysql/slow_queries.log exists, is owned by mysql, and has read/write permission.

---

Turning On Slow Query Logging?
Background: I paid a young admin set me up on a database server. He installed the basic I needed for the server...at my request...No Cpanel...mysql and apache and some tight security w/o even a domain name to SSH into. Unfortunately, he's a busy kid, and teens sometimes don't realize that people depend on them...and well, I can't really seem to get him to do much so I gave up and figured it's a good way to force me to learn all this myself...
Well anyway, now I want to turn on Slow Query logging. But before I do that, I need to know how MySQL is running. Is SQLogging turned on already? Where is it logging to? So first thing I want to look up is, when the server is rebooted, what's the command to restart mysql? No clue. How do I change the setting? And of course, the server is production, so when I make the change, it needs to be quick, it needs to be smooth, and I need to be able to roll back to the previous config if necessary.
I'm running Redhat Enterprise.

---

Help Rewriting A Slow Phpbb Query
I have a "glance" or "Recent Topics" list on my forums that have become fairly complex. I modified an already feature rich glance mod to allow users to select individual forums to exclude from showing topics in the list. As well when users are members of certain forum groups, they see topics from the group forum in the list, and they are highlighted a different colour.

The main SQL query to create the list often is showing up in the MySQL Slow_query log and I'm pretty sure is the main cause for the page loading slow.

I am no mysql Guru, so I thought I would seek the advice of some to improve or totaly rewrite this slow query.

PHP

$sql = "SELECT     
    f.forum_id, f.forum_name, t.topic_title, t.topic_id, t.topic_last_post_id, t.topic_poster, t.topic_views, t.topic_replies, t.topic_type,
    p2.post_time, p2.poster_id,
    u.username as last_username,
    u2.username as author_username
FROM "
    . FORUMS_TABLE . " f, "
    . POSTS_TABLE . " p, "
    . TOPICS_TABLE . " t, "
    . POSTS_TABLE . " p2, "
    . USERS_TABLE . " u, "
    . USERS_TABLE . " u2                
WHERE
    f.forum_id NOT IN (" . $forumsignore . $glance_recent_ignore . ")
    AND t.forum_id = f.forum_id
    AND p.post_id = t.topic_first_post_id
    AND p2.post_id = t.topic_last_post_id
    AND t.topic_moved_id = 0
    AND p2.poster_id = u.user_id
    AND t.topic_poster = u2.user_id
ORDER BY t.topic_last_post_id DESC";
$sql .= ($glance_recent_offset) ? " LIMIT " . $glance_recent_offset . ", " . $glance_num_recent : " LIMIT " . $glance_num_recent;


The "NOT IN" list varies per user, but here is an example:
NOT IN (77,75,76,25,26,37,63,64,66,67,67,1,25,26,37,70,28,75,76,78)

---

Slow Query W/ Join & Ordering
I am trying to figure out why I have a hugely slow query (~2 seconds in my testing environment). Details are below:

It involves two tables, products and vendors.

Products is a huge table, so I will only include the (ostensibly!) relevant fields in its description:

CREATE TABLE `products` (
`id` int(11) NOT NULL auto_increment,
`vendor_id` smallint(6) NOT NULL default Ɔ',
`product_code` varchar(255) NOT NULL default '',
`internal_name` varchar(255) NOT NULL default '',
`lastmodified` timestamp NOT NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,

PRIMARY KEY (`id`),
UNIQUE KEY `product_code` (`product_code`),
KEY `vendor_id` (`vendor_id`)
) ENGINE=MyISAM;
Vendors are much more straightforward:



CREATE TABLE `vendors` (
`id` smallint(6) NOT NULL auto_increment,
`name` varchar(255) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM;
The following query executes in no MORE than 0.01 seconds:


SELECT DISTINCT p.id
, p.product_code
, unix_timestamp(p.lastmodified) as lastmodified
, p.internal_name
FROM products as p
ORDER BY p.product_code ASC
LIMIT 0, 30;
And has the following attributes:

+----+-------------+-------+-------+---------------+--------------+---------+------+-------+-----------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+-------+---------------+--------------+---------+------+-------+-----------------+
| 1 | SIMPLE | p | index | NULL | product_code | 257 | NULL | 25124 | Using temporary |
+----+-------------+-------+-------+---------------+--------------+---------+------+-------+-----------------+
When I join with the vendors table, so that I can fetch the vendor's name for each product, I use the following query, which takes about 1.88 seconds:



SELECT DISTINCT p.id
, p.product_code
, unix_timestamp(p.lastmodified) as lastmodified
, p.internal_name
, v.name as vendor_name
FROM products as p
LEFT JOIN vendors as v ON v.id=p.vendor_id
ORDER BY p.product_code ASC
LIMIT 0, 30;
It has the following characteristics:

+----+-------------+-------+--------+---------------+---------+---------+--------------------------+-------+---------------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+--------+---------------+---------+---------+--------------------------+-------+---------------------------------+
| 1 | SIMPLE | p | ALL | NULL | NULL | NULL | NULL | 25124 | Using temporary; Using filesort |
| 1 | SIMPLE | v | eq_ref | PRIMARY | PRIMARY | 2 | te_inventory.p.vendor_id | 1 | |
+----+-------------+-------+--------+---------------+---------+---------+--------------------------+-------+---------------------------------+
Note the addition of the filesort. I'm unhappy enough about the temporary, which I don't really understand, but the filesort is, I'm fairly sure, killing me.

Closer investigation (or maybe just common sense if you aren't a MySQL newbie like me) shows that the ORDER BY clause is responsible, for when I join without the ORDER BY, my query time goes back down to 0.01 seconds or so:



mysql> explain SELECT DISTINCT p.id
-> , p.product_code
-> , unix_timestamp(p.lastmodified) as lastmodified
-> , p.internal_name
-> , v.name as vendor_name
-> FROM products as p
-> LEFT JOIN vendors as v ON v.id=p.vendor_id
-> LIMIT 0,30;
+----+-------------+-------+--------+---------------+---------+---------+--------------------------+-------+-----------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+--------+---------------+---------+---------+--------------------------+-------+-----------------+
| 1 | SIMPLE | p | ALL | NULL | NULL | NULL | NULL | 25124 | Using temporary |
| 1 | SIMPLE | v | eq_ref | PRIMARY | PRIMARY | 2 | te_inventory.p.vendor_id | 1 | |
+----+-------------+-------+--------+---------------+---------+---------+--------------------------+-------+-----------------+
Any clues on how I can get the execution time to go down when I am sorting? I'm also curious why MySQL is using a temporary table,

---

Mysql 5.0 - Using My.cnf - Unix / Slow-query-log
I installed mysql 5.0 and need to set up slow-query-log and other logging options.

Here is what I did. But I dont see it working yet.

1. cd /var/db/mysql
2. chown mysql slowquery.log
3. touch /usr/local/etc/my.cnf
4. chown mysql /usr/local/etc/my.cnf

vi my.cnf

[mysqld_safe]
-u mysql
--log-slow-queries=/var/db/mysql/slowquery.log

so now when I type:

mysqladmin shutdown
and than

mysqld_safe &
my sql restarts but the log files are not being used.
also - how do I know if my my.cnf is being used at all?

---

Federated Tables Slow? (like 4.5 Hrs For A Query)
I've got a problem with federated tables. I'm using MySQL 5.1 (with InnoDB as the default table type) on a Win2K server, on which I've got four federated tables pointing at four MyISAM tables on a MySQL 4.1.11 server. Of the four tables, three of them run just fine, and I can retrieve data quickly with no problems. The fourth is a sheer pig. While they have different columns, all four tables are roughly as complex as each other, all having the same features and developed by the same team.

The most obvious difference, and what I suspect might be the problem, is that the first three tables have between 150 and 1,000 records, the fourth table has closer to 15,000. Still, there isn't that much lag when I'm pulling from the smaller tables, and the lag is really serious when I'm pulling from the larger one; I ran three queries last night to test, and I could pull data from the smaller tables in about 5 minutes, but the larger table took 4.5 hours- possibly because it was joined with two other tables, but the joins on the smaller tables didn't cause this kind of problem.

The second obvious difference is the fact that I'm pulling from a MyISAM table into a federated table... from which I would like to store into an InnoDB table, but it ends up timing out quite a bit.

Connecting to the database I've federated to isn't a problem. It responds to a PHP frontend lightning-fast. It's just my federated tables that suck so bad. I wouldn't even use federated tables, but I need to pull from the MyISAM database for storing historical records of inventory. What am I doing wrong, and what can I do to speed things up?

---

Slow Inefficent Query (FIXED)
I have this query which pulls members from a table of 1200 members details, filtering out those without and email address and those that don't want Newsletters, and also any whose email address exists in a second table (emails that have hard bounced previously)

My first attempt took an age and returned about 10,000 members, clearly loads of repeated rows

My 'final' attempt with a DISTINCT shoved in works perfectly but is really slow, PHPAdmin says it takes 1.1s but on the website the data doesn't appear for over 30s, all the other sundry queries on the same table work nice and quick on the same website using the same php to generate the table of results

The googling I've done suggests (to me) that there's nothing wrong with the query but I suspect that there's far too much checking of fields going on from the pre DISTINCT query's results ....

---

VER VERY VERY Slow MySQL Query HELP URGENTLY NEEDED
I have the following MySQL query, but it is VERY VERY slow and seems to be crashing the server. There are 300,000+ records in the 'tracker' table.

SELECT sites.*, SUM(if(tracker.type='view',1,0)) AS numberOfViews, SUM(if(tracker.type='click',1,0)) AS numberOfClicks, SUM(tracker.revenue) AS totalRevenue FROM sites LEFT JOIN tracker ON tracker.site_id = sites.id GROUP BY sites.id ORDER BY sites.domain_name

---

Why Does The Slow Query Log Show More Rows Than Exist?
# Time: 070528 17:14:57
# User@Host: counter[counter] @ localhost []
# Query_time: 3 Lock_time: 0 Rows_sent: 7 Rows_examined: 120647
SELECT SQL_CACHE `webpageUrl`, `webpageName`, COUNT(*) AS `count`, (COUNT(*) / (SELECT COUNT(*) FROM _1_log)) AS `pct` FROM _1_log GROUP BY `webpageUrl` ORDER BY `count` DESC LIMIT 7;

mysql> select count(*) from _1_log;
+----------+
| count(*) |
+----------+
| 111824 |
+----------+
1 row in set (0.00 sec)

---

Large Table, Slow Query Question
I have a table with ~800,000 records. I need to grab random rows from the table based on certain criteria. The problem is that average lowest subset to grab the random row is around 200k. Here is what I'm trying to do:

There are 4 columns: data,n1,n2, and n3. I need to get the value of the data column based on criteria using the n1-n3 columns.

The most common query is SELECT data FROM table WHERE n1 = ?

The problem is that n1 can be only 1 of 5 possiblities. When the table is finished being populated there will be roughly 1.5 million records and 250k for each value of n1. Of course, I have an index on each n column.

Right now with just the 800k records it can take over a second, sometimes multiple seconds to run the following in order to get a random row from that subset:

SELECT COUNT(1) AS total FROM table WHERE n1 = 3;
index = random number from 1 to total
SELECT data FROM table WHERE n1 = 3 LIMIT index,1;

How can I speed this up? I need it to take less than half a second if possible. Thank you.

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Slow Execution For A Left Outer Join Query
Whats likely to be the cause of slow execution for a left outer join query?

The original query joins three tables but even if I narrow it down to one it still takes a long time to execute.

$query = "select distinct materials.* from materials";
$query .= " left outer join materials_products on materials.material_id = materials_products.material_id";

There's 914 rows in the materials table and 1348 row in the materials_products table

Is it likely to take a long time for this amount of data or is there likely to be a problem in the table(s) set up or query?

---

Slow
What generally would be the reason why all my db driven sites are running slowly or even hanging. I am on braodband speed but just changed hosts.

---

Slow Authentication
MySQL V 5.0.18 on SUSE 10.1

I'm not a complete *nix noob, but I sure as hell ain't a *nix or MySQL pro.

This is a new installation. Everything screaming fast. Unless it deals w/authentication.

Try to get in w/SQLyog from W2K locally ... intitial connection takes ~20 seconds. Then everything screaming fast.

Web Server (W03) attempts to connect via MyODBC ... same result ... initial connection takes ~20 seconds. Subsequent queries screaming fast.

VNC into the box at any time ... everything fast. (would seem to eliminate network/connection issues)

---

Slow Subselect
I've got two tables:
lo_users: nickname|id|...
lo_friends: from|to|...

The following query takes < 0.01 sec:
SELECT IF(`from` = '10855', `to`, `from`) userid FROM lo_friends WHERE (`from` = '10855' OR `to` = '10855') AND STATUS = '1'

...but if I use it in a subselect, the whole thing takes about 0.54 sec:
SELECT u.nickname FROM (SELECT IF(`from` = '10855', `to`, `from`) userid FROM lo_friends WHERE (`from` = '10855' OR `to` = '10855') AND STATUS = '1') f LEFT JOIN lo_users u ON u.id = f.userid

What can I do to make the query faster? "from" and "to" are indexed and lo_users.id is the primary key.

---

Update Too Slow
I need to update 25 * 5000 records, if I do one at the time it takes too
long time, do any one have a good proposal ?

---

MySQL Slow
I had downloaded a few years back mySQL v3.51 installed but never used it. Now I wanted to convert some B-TREE databases to mySQL and did some testing via ODBC to insert 70,000 records: My results:

MS ACCESS: ~60,000 msecs
MYSQL v3.51 ~18,000 msecs

Impressed with the speed, I went ahead and got the latest MySQL v5.1. Uninstalled the older version, I had nothing there to preserve, so I did a simple new install with MySQL v5.1. I noticed the size of the files and BINEXE increasted by 1,000,000%. Ok, Bulky. Not a problem.

I reran the same ODBC test, and now I got:

MYSQL v5.1: ~450,000 msecs or 7.5 freaking MINUTES!

What the hell happen? Nothing was done. I'm knew to MYSQL. I just installed it with all the defaults. I did choose "developer's machine" for the "optimizer wizard"

I can't redistribute MYSQL v3.51 and force it down people's throats! I have to use what they are using already, if already installed. Not even my current system takes 1 minute to add 70,000 records. Why 7.5 minutes? All it is simple inserts/free statements.

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Join Too Slow
I'm creating a query that use Join clause. I tested it in MySQL 4.0.24 and with MS-ACCESS. . . . in MySQL is slow!!! any suggestion ?

---

Slow Connection
I build an application and installed it on many machines. In every machine except two, the program works without problems. On this two, the connection with database is too slow.

I saw the opened doors with 'netstat' and the computer opens about 5 or 6 ports (to the port 3306 of the mysql server) before sucessfuly connect with MySql Database and execute the sql. I don't know what could be happening. I realy need to fix this because the progrm is too slow with this error. Could anyone know what could be happening??

---

Slow Connect
Does anybody know why it sometimes takes more than 10 seconds to connect to a database and sometimes it just takes half a millisecond?

---

Slow Queries
I had a working web page that queried 20 tables and returned the data in the form of a table ... all of a sudden this stopped returning the results , and on investigation, up to ten tables, the query time is about 0.01 second ... but as the number of tables is increased to fifteen, the query time increases to 60 second .. and then gets too slow with nothing being returned at all.

A few days ago, this was all working fine. There have been no changes to the code on the web page ....
The version of mysql is 4.0.20, the server is a dual 1 MHz Xeon with 512 meg of RAM, running linux.

The tables have up to 15 fields each, and there is only simple text or numerical values in the fields.

Can anyone suggest what might have changed to suddenly slow down the query ?

---

Slow UPDATE
I have a table with the following structure;

CREATE TABLE my_table
(
id_1 int(11) NOT NULL ,
id_2 int(10) NOT NULL ,
stauts tinyint(1) NOT NULL DEFAULT 0 ,
PRIMARY KEY (id_1)
) Engine =InnoDB';


The table currently has arround 100,000 entries. When I try to run variations of the following statement it is taking around 4 seconds per query;

UPDATE IGNORE my_table
SET id_1 = 74240, id_2 = 5

I need it to be running a lot faster than 4 seconds per query as I need to update upwards of 100,000 records a day! My server is fairly beefy, a 3 gig dual core opeteron and is generaly running below 1.0 load.

---

MySQL Very Slow.
I have this one site that slows down all my others because the queries are so massive.

For example one of these queries I use to-do a search by a user's account number. I also get the position he is at on the list, and in order to-do that I need to select ALL the rows.

For example, I filter out the other queries in php.
CODE$num = 1;
$q = mysql_query('SELECT * FROM lists');
while($r = mysql_fetch_assoc($q))
{

   if($r['account']=='accountNum')
   {
         print 'You are at pos. num '.$num.'<br>';
   }
   $num++;
}

---

Why Does MySQL So Slow
I just changed to use MySQL few days ago but it was a bad idea. My server now is running very slowly with the database. I'm using Perl5 and DBD::Mysql in my script. The system is Linux9, Apache2.

I looked at these mysql pid and saw a lot of activities (about 400) while there are more 100 users online at this moment and lots of running under a the same pid number.

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What Causes Slow Queries
What causes periodic slow queries? I have checked my slow query logs and for some reason everyonce in awhile, a query thats never slow might be for example, one took 3 seconds to execute and every once in awhile a chat might take 10 seconds of cpu time while rest of the time 0.09...why is it it flexuates so much?

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Very Slow Select
The line indicated below from my php script is very slow (about 10 seconds). I have this field indexed so I thought that it would be much faster. Could someone tell me what might be wrong?

I'm also including the dump of the table definitions. This is a cd cataloging database.

Right now the filenames table is empty and I'm trying to populate it, but at the rate it's going it would take days. I have about 700,000 records in the 'files' table, but none in the 'filenames' table yet. Code:

---

Slow Running Sql
i am not using mysql but an unknown database system on a unix box - i have no control over the database but have purchased an odbc driver that seems very 'clunky' after using mysql - this is an sql statement question rather than a mysql tech question. if i run this:

SELECT
MK_01_vehicleRecords.registrationnumber, MK_01_VehicleRecords.vehiclenumber
FROM MK_01_VehicleRecords
WHERE (MK_01_VehicleRecords.vehiclenumber = '36176')

---

Slow Connections
I am using MyODBC-3.51.11-2-win on Win 2003 OS. I am not able to see all of the connections in the list under the System DSN tab. The connections that show allow the ASP pages to run at an expected rate.

However, the ones not showing in the list are running extremely slow. If I attpemt to recreate the connection I am told that the connection already exists and asks if I want to replace the existing connection. Wheter I click yes or no the connections do not show and the pages run slowly. How do I get them to show or resolve the issue. The ASP code is the exact same SQL statements and connection strings as the in previous applications.

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Slow Restore
Mysql 4.1.15 on Win2k. Using InnoDB.

Using the mysql administrator gui to create a backup, everything goes
fine, and restores quickly.

Using the command line:

mysqldump %dbname% --single-transaction > %dbname%.sql

creates a file about 15% smaller than the gui produces, and is
EXTREMELY slow to restore. I have tried adding locks, skip opt,
everything. What does the gui use for a command to create this dump?

---

Slow Queries
I just got a new dual opteron system, with raid 01, 2gb ram, and fedora
core linux running 2.4.22-smp kernel. For some reason mysql is running
pathetically slow.

Queries that should take 2ms occasionally take up to
20 seconds. It isn't every time, but almost once per page. The problem
usually occurs with queries accessing the large tables (up to 1gb), but
not always. I've tried 2 versions I compiled myself (with flags
suggested in the readme), as well as the version off the mysql website.
All were 4.0.18, and all had the problem.

---

HEAP So Slow
I have a heap database, with 1.5-1.6 milion rows. on that is 2 columns...

ID | Title

title is indexed. When i run a query like this
------------------
SELECT index_data.* FROM index_data INNER JOIN `index` ON index_data.id=index.id AND index.title LIKE '%$query%' WHERE playtime > $dur... The execution time is about seconds...
------------------
Even a single like statement just on `index` (heap) takes 3-6 seconds.

Here's the table stats...
----------------------------
Data 397,442 KB
Index 24,639 KB
Total 422,081 KB
----------------------------
Why??

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MySQL Slow Log
I have the long query time set to 15 yet MySQL is still showing results with a query time of 0 in the slow query log.

It says enter time in "seconds" in the MySQL Administrator but did it mean in milliseconds??

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Slow Subquery
Can anyone tell me why the following query with sub-query takes forever to finish? (I've le it run for 20 minutes, and it still hasn't finished)

select date from temps where date in (select distinct date from observations where camera like "a")

The sub query returns 10 dates. The outer query is on a table that contains about 40,000 rows. What's the big deal here? All I'm trying to do is select rows from "temps" that match a small range of 10 dates. Is there another way to do this? Is a sub-query the wrong approach?

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Slow Db Access
I have worked with a few mysql dbs on different servers but i have recently been asked to work with one on nicnames. It seems horribly slow. Working in phpMyAdmin (which i had to install myself) it takes ages when i want to do anything. View the table structure, view the data..etc. Any way i can test the speed so that i can compare it against another server i work with and proove there is a speed issue and take it to nicnames cus it is crazy and is going to affect the speed of the website!!

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Slow Performance
On my index.php page, I have a simple query that checks the session_id against a table where I store other session_id'. If it's not there, it records it (unique hit). If it's there, it doesn't record it (not a unique hit.) This usually goes off without a hitch, and every month or so I empty the table.

Right now I only have about 2500 rows, and it's taking forever to load the page. Is there something possibly server related that could be causing this? My host charges an arm and a leg just to see if there's something wrong if I bring up an issue, so I'd like some insight as to whether there's a commonly known server-side issue that can bog down performance.

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Slow Update
The following query can sometimes take up to 2.5 seconds to execute on a table with only 150,000 records.
UPDATE items SET item_views = item_views + 1 WHERE id = 5897;
is there any way I could speed this up? Some setting I could change to make MySQL faster for this?
The field "id" is the primary table key.

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Slow Queries
I have set long query time to 2 seconds in my cnf file. Therefore all the queries taking more than 2 seconds are logged in the file called mysql-slow.log and the file size is 20 Mb.
Is there anyway to sort this file and find out the queries those are taking the most time so that I can optimize only those ones

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Slow MySQL
mySQL has been running very slowly and I am getting errors. First I did 2 things I raised the ServerLimit number (apache) to allow for more connections, I also raised the max conncetions in my.cnf. I do not know if this took effect? That should have worked. But basically in phpmyadmin i get this error frequently. I am getting more traffic so I think it is that.

MySQL said: Documentation
#2002 - The server is not responding (or the local MySQL server's socket is not correctly configured)

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Slow Queries!
I have a website which has a users table in a mySQL database. This users table is large (It has about 25 columns - most varchar(100)) but only has about 10000 records. The records contain user information which is searched with a javascript form.
My problem is that when I click to 'view all', it takes about 7 seconds to load. This seems a lot?
Does 25 cloums seem sxcessive in a table? Can anyone point me to some good tutorials / docs on improving query performance? I have defined the colums as best as I can, but I am using SELECT * from table, would selecting individual columns make a big difference?

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MySQLdb Slow
I have a Python program that parses a file and inserts records into a
database with MySQLdb. I recently upgraded to MySQL 5.0.8, and now my
parser runs *really* slow. Writing out to CSV files is fine, but when I
try to insert the same records in a MySQL5 database, it slows to a
crawl. Using MySQL 4.1 seems fine. The data seems to be inserted
correctly, it's just really slow.

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Order By Super Slow
I have a text field that's indexed. When I try to sort this column (alphabetical), the first page is pretty fast. However, getting to the end, it slows down a lot, taking about 7 seconds just to show the last page of results.

Is there any way to speed up the sorting?

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