Re: why does select * from table oder by indexed_field not use key?

Hi, On Wed, Jul 11, 2012 at 10:31 AM, Reindl Harald h.rei...@thelounge.net wrote: the mysql query optimizer is somehow stupid Its not stupid - remember its not trying to find the best index, rather its trying to find the least costly plan to return the data in the quickest manner. For the

Re: What MySQL-flavor to choose.

Hi, Also after reading Dimitrik blog (http://dimitrik.free.fr/blog/archives/2010/07/mysql-performance-innodb-io-capacity-flushing.html), its seems to me , than one of the thing that are different between the stock mysql (5.5) and xtradb, is the way that they handle IO capacity and flush. So

Re: Does mysql cache strip out /* comments */ first?

Daevid, snip My concern is, my gut tells me that the built in mysql cache system is dumb. And by that I mean, I suspect that mySQL isn't smart enough to strip out comments from the SQL statement string BEFORE storing it as the cache hash key (yet I have no facts either way to back it up and

Re: Does mysql cache strip out /* comments */ first?

be curious why not or what turned you away from it? I work for Percona :o) So I think its best someone else chips in. Ewen -Original Message- From: Ewen Fortune [mailto:ewen.fort...@gmail.com] Sent: Thursday, November 18, 2010 4:56 AM To: Daevid Vincent Cc: mysql Subject: Re: Does

Re: innodb backup

Hi, On Sat, Oct 9, 2010 at 4:21 AM, short.cut...@yahoo.com.cn wrote: Hello, Is there any good document for backup of InnoDB? includes the increment backup and full backup. There is an overview of backups here http://dev.mysql.com/doc/refman/5.1/en/backup-methods.html XtraBackup supports

Re: Best Bin log - type in MYSQL

Vikram, I am using win-server and xp for my master, slave setup. when i do the beginTrans with bin-log = STATEMENT it is causing error. If i defined this with any one of the following, its working quite fine. MIXED, ROW. Which is the best one in the above two? Or how it differs? Can I

Re: Specific benchmarking tool

14, 2009 at 1:23 AM, Johan De Meersman vegiv...@tuxera.be wrote: hmm, I got segfaults. i,ll check after the weekend. On 11/13/09, ewen fortune ewen.fort...@gmail.com wrote: Johan, What does? mk-log-player? - I just used it to split and play back 8G, no problem. Ewen On Fri

Re: Specific benchmarking tool

Johan, The very latest version of mk-log-player can do that. If you get the version from trunk: wget http://www.maatkit.org/trunk/mk-log-player mk-log-player --split Thread_id --type genlog Cheers, Ewen On Fri, Nov 13, 2009 at 4:33 PM, Johan De Meersman vegiv...@tuxera.be wrote: Hey all,

Re: How to REPLACE updating when it's a subset of the primary key what is duplicated or inserting otherwise?

Fernando, On Wed, Oct 7, 2009 at 5:08 PM, Fer C. ferk...@gmail.com wrote: Hello I have a table with a compound primary key (a1,a2) and I want to insert a record (b1,b2) in th cases where there's no a1 value matching b1, and if there's already a b1 value in the form (b1,c2) then just update

Re: Recover data without logs

Weitao, On Sun, May 31, 2009 at 10:13 AM, Weitao Liu liuwt...@gmail.com wrote: I had deleted some important data from my mysql server,who can tell how can I recover my data,I do not open the bin log,is there some other method? If you are using InnoDB you may be able to recovery the data from

Re: Best way to convert character set from latin1 to utf8 for existing database?

Uma, On Mon, Jun 1, 2009 at 8:41 AM, Uma Bhat bhat@gmail.com wrote: Hi All, I have read many blogs suggesting some examples for this. But suggestions from you guys who have ACTUALLY worked on such a scenario would help me out the best. Current Database has: DEFAULT CHARACTER SET -

Re: ibdata1 lost

Sebastien, On Wed, May 27, 2009 at 11:24 AM, Sebastien MORETTI sebastien.more...@unil.ch wrote: Hi, Your data is gone (unless you can undelete it from whatever filesystems you're using). I think it's too late for this, because the MySQL server has been restarted. You may be able to

Re: ibdata1 lost

Sebastien, On Wed, May 27, 2009 at 11:35 AM, Sebastien MORETTI sebastien.more...@unil.ch wrote: I think it's too late for this, because the MySQL server has been restarted. You may be able to recover from the file system. So long as you haven't written lots of data to the file system since

Re: size of database on disk

Hi, On Mon, Apr 27, 2009 at 7:33 PM, Randomcoder randomcod...@gmail.com wrote: Hi, I'm using Mysql on Linux. How can I see the space a certain database is taking on disk ? If you are using MyISAM you can pretty much just use du -sh /path/to/$table Alternatively you can query the

Re: mysqldump failing to load data

Hi, On Thu, Apr 2, 2009 at 1:18 PM, Virgilio Quilario virgilio.quila...@gmail.com wrote: Hi, MySQL v4.1.22 on Linux 2.6.18-6-686 I have a dump file generate with mysqldump created by a version 4.1.10 server. I want to import the dump file into a different server. When I run mysqldump

Re: MySQL versus PostgreSQL for GPS Data

Juan, On Wed, Mar 18, 2009 at 11:14 AM, Juan Pereira juankarlos.open...@gmail.com wrote: Hello, I'm currently developing a program for centralizing the vehicle fleet GPS information -http://openggd.sourceforge.net-, written in C++. The database should have these requirements: - The schema

Re: Does MySQL 5.1 store queries?

Mat, On Tue, Mar 17, 2009 at 2:04 PM, Matthew Stuart m...@btinternet.com wrote: Until recently I have been using 4.0.25 and have just upgraded to 5.1 and just wondered if MySQL now enabled me to store queries in the database rather than have to put them all on my pages. Basically, I want to be

Re: Is there any solution

Kishhna, On Tue, Mar 17, 2009 at 4:13 PM, Krishna Chandra Prajapati prajapat...@gmail.com wrote: Hi list, THE IDEA IS TO HAVE A COMMON LOGIN I have two mysql servers with different databases on each of them. I want to search each databases(few tables) on both the server using a single

Re: what will happen if the disk is full when mysql flush binlog to it

Hi Cui, On Sat, Mar 14, 2009 at 4:33 PM, Cui Shijun rancp...@gmail.com wrote: hi,  What will happen if the disk is full when mysql flush binlog to it?  If I use innodb engine(mysql-5.1.22) and turn on the binlog, is there any chance that mysql has data updated without binlog flushed?  

Re: Why do quotes in an IN() clause effect performance so drastically?

Hi David, On Wed, Feb 18, 2009 at 4:25 AM, Daevid Vincent dae...@daevid.com wrote: I'm really confused. First, I don't understand why quoting my IN() values here caused them to run significantly slower than the non-quoted versions... on just this simple contrived example it can be as much as

Re: [OFFTOPIC] PHP and local-infile

Hi Mauricio, On Wed, Feb 18, 2009 at 12:58 AM, Mauricio Tellez mauricio.tel...@gmail.com wrote: Hi, sorry if this is an offtopic. I have a web site with LAMP, one module use a LOAD DATA LOCAL INFILE statement, all was running fine, but today I ran this module and I get an The used command is

Re: How to get an existing mysql server's build configure option

Hi Ethan, On Fri, Feb 13, 2009 at 10:50 AM, Ethan Chang junchuanzh...@gmail.com wrote: Hi All, I installed a binary mysql version from http://mysql.mirror.kangaroot.net/Downloads/MySQL-5.1/mysql-5.1.31-linux-i686-glibc23.tar.gz I'm curious if I want to make some further personalized build

Re: grabbing even addresses?

Hi Jason, On Mon, Feb 2, 2009 at 7:27 PM, Jason Pruim japr...@raoset.com wrote: Hello! I was wondering if something was possible, I have an excel file right now of US mailing addresses, and what I need to do is select all the odd numbered addresses on one road, is there an easy way I can do

Re: Restarting MySQLD when all transactions are complete

Hi, On Wed, Jan 14, 2009 at 3:00 PM, John Daisley john.dais...@mypostoffice.co.uk wrote: Hi, Probably a simple question for someone who knows :) Is there a way to force MySQLD to restart after it has finished processing all current transactions? I seem to remember from the bit of Oracle

Re: Performance tips

Hi, On Sat, Dec 27, 2008 at 6:15 PM, Chris Picton ch...@ecntelecoms.com wrote: Hi I am trying to get to grips with understanding mysql performance. I have the following query: select sql_no_cache count(*), date_format(calldate, '%y-%m-%d') as m from cdr_warehouse group by m; This gives

Re: Performance tips

Extra: Using index Cheers, Ewen On Sat, Dec 27, 2008 at 8:04 PM, ewen fortune ewen.fort...@gmail.com wrote: Hi, On Sat, Dec 27, 2008 at 6:15 PM, Chris Picton ch...@ecntelecoms.com wrote: Hi I am trying to get to grips with understanding mysql performance. I have the following query

Re: MySQL 5.0.67 on SMP

Hi, I think the known problems with MySQL and SMP architecture are more based on storage engine restrictions, so InnoDB for example does not scale well beyond say 8 cores. There are a number of patches to help solve some of these scaling problems. http://www.percona.com/docs/wiki/release:start

Re: MySQL Guru Needed!!

As an alternative you also have www.percona.com www.pythian.com www.openquery.com.au www.provenscaling.com Percona's minimum billing unit is 15 minutes, not sure about the rest On Dec 12, 2008, at 17:35, bruce bedoug...@earthlink.net wrote: Hi. I've got a situation where I need to reach

Re: Replication

Hi, On Mon, Dec 8, 2008 at 9:20 AM, Marcel Grandemange [EMAIL PROTECTED] wrote: WHat errors are you getting when you try and start the slave? That's the exact thing mysql show slave status\G *** 1. row *** Slave_IO_State:

Re: Replication

Hi Marcel, On Fri, Dec 5, 2008 at 2:02 PM, Marcel Grandemange [EMAIL PROTECTED] wrote: Good Day. Im wondering if someone can assist me. Ive been using replication for a while now and it tends to fail very easily. Do you have the error messages?. One of my sites lost connectivity for a

Re: Mysql and Flashback

Hi Shain, If you are using InnoDB its possible to patch to allow this functionality. Percona are in the early stages of developing a patch specifically to allow flashback type access to previous table states. https://bugs.launchpad.net/percona-patches/+bug/301925 If you wanted to go down the

Re: Calculate total size of InnoDB tables?

Hi, You can get that from the information_schema, check out this post from Peter Zaitsev http://www.mysqlperformanceblog.com/2008/03/17/researching-your-mysql-table-sizes/ Ewen On Fri, Sep 12, 2008 at 10:25 PM, Ryan Schwartz [EMAIL PROTECTED] wrote: Is there an easy way to calculate the

Re: INDEXING ALL COLUMNS

Hi, Following on from what Mike mentioned, indexing all columns does not really help as MySQL will at most use one index for a query, so its important to pick your indexes carefully and consider constructing composite indexes. An index on a single column may not even be used due to poor

Re: INDEXING ALL COLUMNS

default '0', param varchar(128) NOT NULL default '', value varchar(128) default NULL, PRIMARY KEY (student_id,param). KEY idx_value (value) ) On Sat, Sep 6, 2008 at 1:16 AM, ewen fortune [EMAIL PROTECTED] wrote: Hi, Following on from what Mike mentioned, indexing all columns does

Re: sync

Hi, Have you tried mk-table-sync from the Maatkit toolset http://www.maatkit.org/tools.html Ewen On Mon, Sep 1, 2008 at 2:12 PM, Mad Unix [EMAIL PROTECTED] wrote: I was wandering if anyone know a good way to sync 2mysql databases _one_way The mysql is alocated on a web php application.

Re: escape a dash in table name

Using backticks `temp-08-08-28` Cheers, Ewen On Thu, Aug 28, 2008 at 1:01 PM, Dan O'Keefe [EMAIL PROTECTED] wrote: How do you escape a dash in a table name such as temp-08-08-28? Thanks, Dan -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:

Re: delaying replication

Hi, You do this with mk-slave-delay from the Maatkit toolkit. http://www.maatkit.org/tools.html This tool implements delayed replication on the slave by sampling binlog positions, then starting and stopping the slave as needed to make the slave lag its master by a specified amount. It does not

Re: CONCAT doesn't work with NULL?

Hi Afan, You can use concat_ws http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_concat-ws --- CONCAT() returns NULL if any argument is NULL. CONCAT_WS() does not skip empty strings. However, it does skip any NULL values after the separator argument --- Ewen On Wed, May 14,