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Re: [Maria-discuss] Index bug in aria engine?
by pslawek83 07 Mar '14

07 Mar '14

Ok i wasn't able to reproduce the issue fully, now data is different ... but again, "skipped rows" number changes, and index sizes differ a lot: Uniq index: http://screencast.com/t/SrBS1L5xeB8 http://screencast.com/t/3dVMU7b69AH2 Normal index: http://screencast.com/t/Zl5Jm2OZ http://screencast.com/t/P3SA8U6duly But again, unique index is working much worse than not unique... while it's bigger http://screencast.com/t/rjexoWKwFF http://screencast.com/t/qYdsmRbRbmG7 I'll quickly explain how tables were created... i first took part of the data with unique index, and made smaller copy, thats table 1 Then i just copied the table changed the index to non-unique. After this i copied the tables once again to be sure files are not fragmented, etc. SHOW WARNINGS returns nothing in both cases. It seems that the additional knowledge (only single row with same data) should make the optimizer and query behave better but it's actually behaving much worse... -- Query for reference: EXPLAIN extended SELECT attrib_id, raw_stats_value_id, sum(impressions)FROM raw_stats_other_copyi1_copy INNER JOIN raw_stats_lookupON raw_stats_lookup_id = raw_stats_lookup.idWHERE domain = 'mydomain.com'AND date = '2014-02-10'GROUP BY attrib_id, raw_stats_value_id; -- Thanks, Slawomir. Dnia 6 marca 2014 17:46 Sergei Golubchik <serg(a)mariadb.org> napisał(a): Hi, pslawek83! On Feb 17, pslawek83 wrote: > Hi Guys, > any comments on this issue? It seems that partial unique indexes can't be used in joins. > https://mariadb.atlassian.net/browse/MDEV-5663 Please, show EXPLAIN EXTENDED (and SHOW WARNINGS after it) for this query of yours. > * Why the server is treating same indexes differently depends on if > they're UNIQUE or not It doesn't, there're almost no differences between UNIQUE and non-unique indexes from the optimizer point of view. Optimizer knows that for a unique index there can be at most one matching row (if all index parts are known and are NOT NULL), for non-unique indexes there can be more. That's basically the only difference. > * That's probably not optimizer issue, as we can't FORCE the index You cannot force the index if it is not applicable at all. > * What's internal difference between unique and non-unique index (eg. > memory / file representation / data structure) none. > * What each index type is suitable for, considering query optimization > (as there's no data i was able to find on topic) Aria only supports BTREE indexes anyway. Regards, Sergei

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[Maria-discuss] Index bug in aria engine?
by pslawek83 06 Mar '14

06 Mar '14

Hi Guys, any comments on this issue? It seems that partial unique indexes can't be used in joins. https://mariadb.atlassian.net/browse/MDEV-5663 Regards,

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[Maria-discuss] New Question: mariaDB for arm
by AskMonty KB 05 Mar '14

05 Mar '14

Hello, A new question has been asked in "MariaDB community" by mikestorcheous: -------------------------------- А не подскажите репозиторий для debian 7 armhf? -------------------------------- To view or answer this question please visit: http://mariadb.com/kb/en/mariadb-for-arm/

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[Maria-discuss] MariaDB & MySQL community event 3rd of April 2014 in Santa Clara
by Michael Widenius 05 Mar '14

05 Mar '14

Hi! I am happy to announce that the MariaDB Foundation is organising a MariaDB & MySQL community event in Santa Clara on Thursday the 3rd of April. The venue is the Hilton Santa Clara hotel, a short walk from the Percona Live 2014 event. You can find more information on my blog at: http://monty-says.blogspot.fi/2014/03/mariadb-mysql-community-event-2014-in… We already got some very interesting talks and speakers, but I would like to see even more talk proposals. It's ok to propose a talk that it's also hold at Percona Live. As this event is free, I expect a totally different group of attendees, so that should be fine! When we have got a nice list of proposed talks, we will post them here so that everyone has a chance of commenting of which talks should be accepted. (Sorry, but this time we don't have time to create a proper selection committee so we have to do this a bit rough) Personally I will talk about MariaDB 10.0, which should be declared stable by then. Hope to see many MariaDB developers and users in Santa Clara! You can sign up for the event and/or dinner at: http://www.eventbrite.com/e/mariadb-mysql-community-event-2014-tickets-1080… Regards, Monty PS: Feel free to discuss the event on this email list! We want to have as many as possible participating in making this the best possible MariaDB and MySQL event.

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[Maria-discuss] New Question: Downloaded; how do I install?
by AskMonty KB 28 Feb '14

28 Feb '14

Hello, A new question has been asked in "MariaDB Documentation" by jeffreythomas: -------------------------------- I've downloaded MariaDB; how do I install it? Thanks, Jeff -------------------------------- To view or answer this question please visit: http://mariadb.com/kb/en/downloaded-how-do-i-install/

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[Maria-discuss] New Question: Maria DB - changing hosting with a different DB
by AskMonty KB 26 Feb '14

26 Feb '14

Hello, A new question has been asked in "MariaDB community" by hannasles: -------------------------------- Hi Guys! I am moving my web-site from one hosting to another. The DB on the first hosting is MariaDB, DB on the hosting I am moving to is MyIsam. When importing the DB, I am getting this message: ERROR 1064 (42000) at line 19: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'PAGE_CHECKSUM=1' at line 6 Line 19 runs: CREATE TABLE `wp_blc_filters` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `name` varchar(100) NOT NULL, `params` text NOT NULL, PRIMARY KEY (`id`) ) ENGINE=Aria DEFAULT CHARSET=utf8 PAGE_CHECKSUM=1; As I am not good at all with DB and my hosting supports can not answer my enquiries, I have to open this question here. I will really appreciate that if you could help me with this! -------------------------------- To view or answer this question please visit: http://mariadb.com/kb/en/maria-db-changing-hosting-with-a-different-db/

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[Maria-discuss] New Question: How do I keep the graph table and data table in sync?
by AskMonty KB 26 Feb '14

26 Feb '14

Hello, A new question has been asked in "OQGRAPH" by prestonthayne: -------------------------------- So I added some rows to the data table before I created the graph table that then showed up just fine. I then added some more rows to the data table and did a select * on the graph table and the new rows weren't there. I did a shortest route query and they showed up. A subsequent select * query to the graph table and they were there. What triggered them to appear? I then added a few more and no matter what I do they won't show up. The last one that won't show up was a two way link ( insert into oq_backing (origid,destid) values (9,10),(10,9) ). That's not a problem is it? And lastly, is there any good documentation/literature around for how oqgraph works and how to use it? Thanks, Preston -------------------------------- To view or answer this question please visit: http://mariadb.com/kb/en/how-do-i-keep-the-graph-table-and-data-table-in-sy…

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[Maria-discuss] MariaDB 5.5.36 now available
by Daniel Bartholomew 25 Feb '14

25 Feb '14

The MariaDB project is pleased to announce the immediate availability of MariaDB 5.5.36. This is a Stable (GA) maintenance (bug fix) release. See the Release Notes and Changelog for details. - - Links - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - MariaDB 5.5.36 - Release Notes: https://mariadb.com/kb/en/mariadb-5536-release-notes - Changelog: https://mariadb.com/kb/en/mariadb-5536-changelog - Downloads: https://downloads.mariadb.org/mariadb/5.5.36 About MariaDB 5.5: - https://mariadb.com/kb/en/what-is-mariadb-55/ APT and YUM Repository Configuration Generator: - https://downloads.mariadb.org/mariadb/repositories/ - - MariaDB Webinars - - - - - - - - - - - - - - - - - - - - - - - - - SkySQL has held several MariaDB-focused Webinars recently which are available on an on-demand basis at: - http://www.skysql.com/why-skysql/webinars/ They are also planning several more MariaDB-focused webinars that will be held over the comming months. Details available at the above link. - - MariaDB Book - - - - - - - - - - - - - - - - - - - - - - - - - - - - Getting Started with MariaDB A how-to guide for beginners to help them get up to speed quickly with MariaDB, no previous MariaDB or MySQL experience required. http://www.packtpub.com/getting-started-with-mariadb/book - - User Feedback plugin - - - - - - - - - - - - - - - - - - - - - - - MariaDB includes a User Feedback plugin. This plugin is disabled by default. If enabled, it submits basic, completely anonymous MariaDB usage information. This information is used by the developers to track trends in MariaDB usage to better guide development efforts. If you would like to help make MariaDB better, please add "feedback=ON" to your my.cnf or my.ini file! See http://mariadb.com/kb/en/user-feedback-plugin for more information. - - Quality - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - The project always strives for quality, but in reality, nothing is perfect. Please take time to report any issues you encounter at: - http://mariadb.org/jira - - Support MariaDB - - - - - - - - - - - - - - - - - - - - - - - - - - If you would like to contribute to the MariaDB Foundation, please see the "contributing" and "donations" pages. We also have merchandise available in a cafepress store. All proceeds go to support the MariaDB Foundation. - https://mariadb.com/kb/en/contributing - https://mariadb.org/en/donate/ - http://www.cafepress.com/mariadb We hope you enjoy MariaDB! -- MariaDB: An Enhanced Drop-in Replacement for MySQL Website - http://mariadb.org Twitter - http://twitter.com/mariadb Google+ - http://google.com/+mariadb Facebook - http://fb.com/MariaDB.dbms Knowledge Base - http://mariadb.com/kb

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[Maria-discuss] New Question: Unknown option 'table_data' OQGraph in MariaDB 10.0.7
by AskMonty KB 25 Feb '14

25 Feb '14

Hello, A new question has been asked in "OQGRAPH" by prestonthayne: -------------------------------- I am trying to evaluate MariaDB and OQGraph and am having difficulty creating the tables. I follow the examples exactly as on the site. I create the backing table, I insert some data into the backing table, I attempt to create the graph table and I get an error that the option 'table_data' is unknown. I am using MariaDB 10.0.7 on CentOS 6.5. Any advice would be greatly appreciated. Preston -------------------------------- To view or answer this question please visit: http://mariadb.com/kb/en/unknown-option-table_data-oqgraph-in-mariadb-1007/

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[Maria-discuss] We are participating in Google Summer of Code 2014
by Colin Charles 25 Feb '14

25 Feb '14

Hi, It is with great pleasure that I can inform you that we have been accepted as an organisation to participate in Google Summer of Code 2014! It would be great to see more ideas pop up here: https://mariadb.com/kb/en/google-summer-of-code-2014/ More mentors are always wanted! I presume we will see a lot more student discussions here as well. If you have any questions that aren't answered on the lists, please send me a personal note Here's to more features & contributors in 2014. cheers, -colin -- Colin Charles, Chief Evangelist MariaDB | t: +6-012-204-3201 | Skype: colincharles

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