Mysql 4.1 vs 5.0
Benching Somebody knows why 4.1 is faster than 5.0 mysql versions Ing. Jaime Fuentes R. 997500459 2421905-2423252 Enviado desde mi BlackBerry de Claro. -Original Message- From: Brent Baisley brentt...@gmail.com Date: Tue, 2 Jun 2009 12:32:39 To: Rayr...@stilltech.net Cc: mysql@lists.mysql.com Subject: Re: Question about query - can this be done? On Tue, Jun 2, 2009 at 11:52 AM, Ray r...@stilltech.net wrote: Hello, I've tried the manual and google, but I am not even sure what to call what I want to do. simplified data example: I have a table of start and end times for an event, and an id for that event in a table. each event may occur multiple times, but never more than 5 times and rarely more than 3. I want a query that will provide one record per event with all times included. feel free to answer RTFM or STFW as long as you provide the manual section or key words. ;) Thanks, Ray chart form follows: id | event_id | start | end --- 1 | 4 | t1 | t2 2 | 4 | t3 | t4 3 | 4 | t5 | t6 4 | 5 | t1 | t2 5 | 5 | t3 | t4 becomes id | event_id | start | end | start | end | start | end --- ? | 4 | t1 | t2 | t3 | t4 | t5 | t6 ? | 5 | t1 | t2 | t3 | t4 I think what you are looking for is GROUP_CONCAT. You can just GROUP BY event id, and then process the resulting delimited string on the front end. SELECT event_id, GROUP_CONCAT(start) start_dates, GROUP_CONCAT(end) end_dates FROM events GROUP BY event_id Or even combined start and end dates into a single string and group them. SELECT event_id, GROUP_CONCAT( CONCAT(start, '-', end) ) start_end FROM events GROUP BY event_id But, if you really want to get it in the column format you indicate, you can make a much more complicated query. Use SUBSTRING_INDEX to split out the parts of the group you need. SELECT event_id, SUBSTRING_INDEX(GROUP_CONCAT(start), ',', 1 ) start1, SUBSTRING_INDEX(GROUP_CONCAT(end), ',', 1 ) end1, SUBSTRING_INDEX( SUBSTRING_INDEX(GROUP_CONCAT(start), ',', 2 ), ',', -1 ) start2, SUBSTRING_INDEX( SUBSTRING_INDEX(GROUP_CONCAT(end), ',', 2 ), ',', -1 ) end2, SUBSTRING_INDEX( SUBSTRING_INDEX(GROUP_CONCAT(start), ',', 3 ), ',', -1 ) start3, SUBSTRING_INDEX( SUBSTRING_INDEX(GROUP_CONCAT(end), ',', 3 ), ',', -1 ) end3, SUBSTRING_INDEX( SUBSTRING_INDEX(GROUP_CONCAT(start), ',', 4 ), ',', -1 ) start4, SUBSTRING_INDEX( SUBSTRING_INDEX(GROUP_CONCAT(end), ',', 4 ), ',', -1 ) end4, SUBSTRING_INDEX( SUBSTRING_INDEX(GROUP_CONCAT(start), ',', 5 ), ',', -1 ) start5, SUBSTRING_INDEX( SUBSTRING_INDEX(GROUP_CONCAT(end), ',', 5 ), ',', -1 ) end5 FROM events GROUP BY event_id; I think that will give the format you specified, but I am not recommending you do it this way. Hope that helps. Brent Baisley -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/mysql?unsub=jfuen...@segursat.com
Re: too many connections
You have to use mysql 64bits on S.O. 64bits --Mensaje original-- De: Martin Gainty Para: Kinney, Gail Para: 'mysql@lists.mysql.com' Enviado: 19 Sep 2008 10:51 Asunto: RE: too many connections in my.cnf configuration file try upping the number of connections max_connections=3072 to max_connections=6144 Martin __ Disclaimer and confidentiality note Everything in this e-mail and any attachments relates to the official business of Sender. This transmission is of a confidential nature and Sender does not endorse distribution to any party other than intended recipient. Sender does not necessarily endorse content contained within this transmission. From: [EMAIL PROTECTED] To: mysql@lists.mysql.com Date: Fri, 19 Sep 2008 09:33:58 -0600 Subject: too many connections Hello, We have MySQL 4.0.14 and have just gotten an error: too many connections. we can't connect to our site using MySQL admin. Please help. Gail Kinney Webmaster UC Denver [EMAIL PROTECTED]mailto:[EMAIL PROTECTED] _ Want to do more with Windows Live? Learn “10 hidden secrets” from Jamie. http://windowslive.com/connect/post/jamiethomson.spaces.live.com-Blog-cns!550F681DAD532637!5295.entry?ocid=TXT_TAGLM_WL_domore_092008 Enviado desde mi BlackBerry de Claro.
mysql x64en server 64 bits
Hi every body: I've a Server with Intel quad Core processor + Wndows 2003 server R2 64 bits, I'm trying to install a myql 5.1 x64 but it shows me that this installation package is npot supported by this processor type. Contact your vendor. What could be happening ? please help me Urgent. Jaime Fuentes R. Peru Arpotu escribió: All, I have a customer who has been on MySQL for about 8 years, but they are moving their business elsewhere. They are moving their database into an Oracle shop, and want me to export their MySQL data into a format that's easily imported into Oracle. Does anyone have experience doing this, or are there migration tools? A flatfile export has been suggested, but I'm not sure if they'll need to maintain data types in the export. Ideas? Thanks, Arpotu. -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: procedure locks all statemens
Hi Last days frequently I see an error message : Can't create a new thread (errno 12) if you are not out of available memory, you can consult the manual for a possible OS-dependent bug. mysql is 5.0.41 server RAm: 2Gb and 100 Gb free spaces hard disk users around 64 Into my.ini the max_connection parameter is 2048. what could be happened? and what to solve this ? Jaime Fuentes R.
HELP: mysql stoped sudenly , Database page corruption on disk or a failed
Dear Friends: since 2 weeks ago the mysql is stoping sudenly, and into the error log is as lines below, Database page corruption on disk or a failed , file read of page 34, how I can know what table is in page 34 ? I've used mysqlcheck, without any result, all is OK for it, mysql 4.01 is running on windows 2003 and the ibdata1of innodb is 20 GB Thanks in advance Jaime 070228 17:44:04 InnoDB: Page checksum 75769562, prior-to-4.0.14-form checksum 3189442283 InnoDB: stored checksum 4088203197, prior-to-4.0.14-form stored checksum 0 InnoDB: Page lsn 0 36808, low 4 bytes of lsn at page end 0 InnoDB: Page number (if stored to page already) 34, InnoDB: space id (if created with = MySQL-4.1.1 and stored already) 0 InnoDB: Database page corruption on disk or a failed InnoDB: file read of page 34. InnoDB: You may have to recover from a backup. InnoDB: It is also possible that your operating InnoDB: system has corrupted its own file cache InnoDB: and rebooting your computer removes the InnoDB: error. InnoDB: If the corrupt page is an index page InnoDB: you can also try to fix the corruption InnoDB: by dumping, dropping, and reimporting InnoDB: the corrupt table. You can use CHECK InnoDB: TABLE to scan your table for corruption. InnoDB: See also http://dev.mysql.com/doc/mysql/en/Forcing_recovery.html InnoDB: about forcing recovery. InnoDB: Ending processing because of a corrupt database page. 070228 17:45:07 InnoDB: Database was not shut down normally! InnoDB: Starting crash recovery. InnoDB: Reading tablespace information from the .ibd files... InnoDB: Restoring possible half-written data pages from the doublewrite InnoDB: buffer... 070228 17:45:07 InnoDB: Starting log scan based on checkpoint at InnoDB: log sequence number 29 4030208738. InnoDB: Doing recovery: scanned up to log sequence number 29 4030343563 070228 17:45:07 InnoDB: Starting an apply batch of log records to the database... InnoDB: Progress in percents: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 InnoDB: Apply batch completed 070228 17:45:09 InnoDB: Flushing modified pages from the buffer pool... 070228 17:45:09 InnoDB: Started; log sequence number 29 4030343563
