Index Query Tunning

Hi All, I have situation here about Innodb locking. In  transaction, We select from XYZ transaction table values and then updates it like below SESSION 1: START TRANSACTION; SELECT ID INTO vID FROM XYZ WHERE FLAG = 1 ORDER BY TIME LIMIT 1 FOR UPDATE; UPDATE XYZ SET FLAG=0 WHERE ID = vID; COMMI

Index locking Query

Hi All, I have situation here about Innodb locking. In  transaction, We select from XYZ transaction table values and then updates it like below SESSION 1: START TRANSACTION; SELECT ID INTO vID FROM XYZ WHERE FLAG = 1 ORDER BY TIME LIMIT 1 FOR UPDATE; UPDATE XYZ SET FLAG=0 WHERE ID = vID; COMMIT

Re: Monitoring Sessions

Thanks Johan for info, We already tried with tcpdump and wireshark it was helpfull. Percona tool kit i need to try. From: Johan De Meersman To: Anupam Karmarkar Cc: mysql@lists.mysql.com Sent: Wednesday, 10 October 2012 5:16 PM Subject: Re: Monitoring

Monitoring Sessions

Hi All, How to monitor individual session number of rows selected or updated by sessions, number of bytes sent and reviewed by session in a given time period, sessions connects runs command and then disconnects, SHOW GLOBAL STATUS is not helping me in this case as i want low level session detai

Re: Need Query Help

Thanks Rick for your reply, Here i am asking about logic to perpare query or whole query itself. --Anupam From: Rick James To: Anupam Karmarkar ; "mysql@lists.mysql.com" Sent: Wednesday, 20 June 2012 10:52 PM Subject: RE: Need Query H

Need Query Help

Hi All, I need query help for following table struture, where we need to calculate login duration of that employee for give period. Example table EmployeeID     LoginTime   LogoutTIme 101            2012-05-01 10:00:00     2012-05-01 12:30:00 102            2012-

Re: Architectural Help

Dear Nigel, Thank for reply.. See my comments below --Anupam From: Nigel Wood To: Anupam Karmarkar ; "mysql@lists.mysql.com" Sent: Thursday, 24 May 2012 3:35 PM Subject: RE: Architectural Help A few questions: which is more or a proble

Architectural Help

Hi All, I need architectural help for our requirement, We have nearly 50 data centre through out different cities from these data center application connect to central database server currently, there are conectivity and nework flcutions issues for different data center, so we comeup with s

Re: Join 2 tables and compare then calculate something

Try out query with UNION also select A,B,C from (select A,B,C from X UNION select A,B,C from Y) group by A,B,C having count(*)>1 From: Gian Karlo C To: mysql@lists.mysql.com Sent: Sunday, 2 October 2011 12:49 PM Subject: Join 2 tables and compare then calculat

Re: replication between two tables in same database

Try out functionality you desire with trigger to replicate data From: Derek Downey To: [MySQL] Sent: Thursday, 29 September 2011 10:46 PM Subject: Re: replication between two tables in same database You could look into the sphinx engine http://sphinxsearch.com

Schema list

There is one database name 'XYZ' on linux system, some one has mistakenly created new database name with 'xYZ', database is created when I use 'xYZ' database, there are no tables with SHOW TABLES, but when i run SHOW PROCEDURE STATUS it show procedures from 'XYZ' database. My concern is that if

Replication Sync Error

Hi All, We are running semi-sync replication on production server, last week found out that replication suck at some event schedule created at master, as that was not important i skipped that started replication again, found out that slave is days behind at master, i invested gate more and foun

Re: Fastest Select

, Johan De Meersman wrote: From: Johan De Meersman Subject: Re: Fastest Select To: "Claudio Nanni" Cc: mysql@lists.mysql.com, "Anupam Karmarkar" Date: Wednesday, 8 June, 2011, 10:53 AM - Original Message - > From: "Claudio Nanni" > > how do yo

Fastest Select

Hi All, We have very big table with few column contains nearly 10 million records, We need to tune this table for simple select statement where we check record exists in table or not and  requirement is response time should be less than 10 million second for nearly 1000 concurrent requests, wha

Re: Help with a query

Hi Aveek, You need to use something like union all and having to get desire result Follow example below select file, digest  from ( SELECT file, digest,Count(*)  as Cnt FROM A GROUP BY file, digest union all SELECT file, digest,Count(*)  as Cnt FROM B GROUP BY file, digest ) tmp group by file,

RE: Complex Query

Hi Guido, You need to add group by in your query get desire result SELECT IFNULL(image,'no_image.jpg') as image,title, subtitle, group_concat(concat(fname,' ',initial,' ',lname)) as author, pkisbn, publisher FROM book INNER JOIN publisher on pkpublisher_id = fkpublisher_id INNER JOIN module_bo

Re: innodb system variable

Hi All innodb_rollback_on_timeout=1 Specifies when there is transaction open by session and not committed, If such session is inactive for long time, MySQL by default kicks out such session and transaction perform by session would be rollback innodb_lock_wait_timeout=600 Specify wait for loc