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1answer
17 views

MongoDB Storage Engine

How can I change the storage engine of MongoDB permanently so that I don't have to run mongod without having to specify the storage engine every time? I am using shell version 3.2.7 on Windows 7 32-...
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1answer
32 views

Mysql read only engine type and indexes

I have a mysql table. This table has only three columns. Two are varchar (5),and one is varchar (32). There will only be one query run against table. Select (column 1),(column 2) from mytable where ...
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1answer
79 views

howto read/interpret “show engine innodb mutex” output?

We use a 3 node Galera cluster with version 5.5.41-MariaDB-wsrep MariaDB [(none)]> show engine innodb mutex; +--------+---------------------------------+------------------+ | Type | Name ...
10
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1answer
507 views

Do databases make a delete and an insert when having to update rows?

So today a professor told us that when the database has to make an update, internally (at low level) it makes a delete and then an insert with the updated fields. He then said that this is something ...
2
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2answers
29 views

MySQL lock on MEMORY storage engine, when does it apply?

I want to use MySQL MEMORY storage engine to handle my PHP session variables (actually I already implemented it but since all my tests are being done by a single user, me, I am unable to notice this). ...
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1answer
36 views

Does TokuDB need any regular cleanup/maintenance?

PostgreSQL has vacuum and InnoDB has purge. Does TokuDB have any required maintenance/cleanup operations? I couldn't find anything in the online docs: https://www.percona.com/software/mysql-database/...
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0answers
91 views

Is the Aria storage engine really crash safe?

I maintain a PHP/MySql app for a big customer. Many of the tables were on MyISAM b/c that was the default when I started. On a newer server running MariaDB, some of those tables kept crashing. ...
2
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1answer
32 views

Alternative ways to find tables with specific storage engine?

I have a VPS with three accounts and 5 db's. Recently I added MySQLTuner. All of my tables are MyISAM, but the results MySQLTuner are showing that I have 14 tables that use InnoDB. [--] Data in ...
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2answers
5k views

MongoDB MMAPv1 vs WiredTiger storage engines

In mongoDB3 appeared a new storage engine: WiredTiger. Yet, MMAPv1 is still the default choice in Mongo. One might not be better than the other, it's often a matter of use case and choosing the ...
0
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2answers
49 views

What storage engine do I need - Mysql?

I have designed a database and came to the point of actually deciding which storage engine is better for my case. I estimate that during the first few years I would have around 100,000 - 500,000 ...
2
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1answer
91 views

SQLyog and MariaDB engine

I am quite new in MariaDB and I use SQLyog Community Edition as the frontend GUI. Whenever I create a new table, on the Engine dropdown, there is no XtraDB option. Is there any additional steps I am ...
3
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1answer
166 views

MariaDB Spider Engine Out of Memory

I had almost standard MariaDB with InnoDB engine working fine but I wanted to test out the Spider Engine + Sharding/Partitioning. I had a query which was passing fine on the MariaDB InnoDB for 15-...
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2answers
230 views

Optimal engine for small lookup tables in MySQL

I have following question: I am designing web application with several dozens of small lookup tables: These tables usualy contain three columns (ID, Name, Description) and a couple of rows (mostly ...
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3answers
4k views

Migrate Jira to MySql - Unknown system variable 'storage_engine'

I'm migrating JIRA in Windows from HSQL to MySQL and I got stuck with the message Unknown system variable 'storage_engine'. Though I created a backup, installed MySQL and copied J connector to libs ...
5
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1answer
2k views

MongoDB 3.0 : Configure storage engine at collection or database level

I know we can configure the storage engine to be wiredTiger at instance level when we start mongod. But can we also select the storage engine to be different for different collection or database?
0
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1answer
98 views

Change Storage Engine on Referenced Tables

i need to change storage engine from 'InnoDB' to 'MyISAM' on some tables of different databases. So i made a script file to do so: #!/bin/bash DATABASES=$(mysql -u XXXXX -pXXXXX --skip-column-names -...
2
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1answer
326 views

Mysqli prepare error: Unknown storage engine 'InnoDB'

I'm getting this error on my XenForo installation. Server logs show out of memory because of too many php processes opened up which cause mysqld to shutdown. The WordPress installation associated with ...
0
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0answers
366 views

I have changed table engines from MyISAM to Aria, should I change the database engine too?

I have changed all tables in my mariadb database from MyISAM to Aria (using adminer as tool), but the database engine is still shown as InnoDB. Should I change this to Aria, too? I did not choose ...
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1answer
235 views

How do I create fractal index using tokudb engine?

I install MariaDb and configured it to use TokuDb Engine. I need to use Fractal-Index Built-in on TokuDb Engine. I have create my index as follow: ALTER TABLE `table__name` ADD INDEX ( `column` ); ...
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1answer
470 views

How to export mysql databases with different ENGINE?

I'm setting up MySQL Cluster. As it uses ENGINE=NDBCLUSTER, how could I export my databases from MySQL Server specifying the ENGINE? Is there a way to do this? All my tables are MYISAM
1
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1answer
155 views

Fastest engine for Mass Updates (only updates done on table)

I have a table of 2 columns and 60 million rows. I want to update the table by incrementing one field by 1 on various different rows (This is the only type of operation that will ever be done on the ...
1
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1answer
87 views

How Much Resources Does the BLACKHOLE Storage Engine Consume?

I'm going to add a MySQL Relay Slave which use BLACKHOLE Storage Engine. The relay slave will just filter some databases binlog to downstream slave. Our MySQL Master generates about 15G a day in ...
5
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1answer
720 views

Is it Possible to Recover Data from a BLACKHOLE table? [closed]

I had created table with engine BLACKHOLE basically the BLACKHOLE storage engine acts as a “black hole” that accepts data but throws it away and does not store it. Retrievals always return an empty ...
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2answers
1k views

Is there a way to enable MariaDB MEMORY storage engine for every table?

I am new to MariaDB and interested in using it because I want to use MEMORY storage engine for every table. I read MEMORY storage engine on mariadb.com and it seems like I had to specify storage ...
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1answer
1k views

InnoDB to MyISAM Conversion Problem

I have a dedicated server based on CentOS 5 OS , mysql 5 and phpmyadmin I was trying to convert all database tables from InnoDB to MYISAM. I tried to do it by setting in /etc/my.cnf file the value ...
0
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1answer
178 views

Aria engine - changing block size

It's possible to change aria_block_size from default 8192 without recreating tables? I want try 1024 or 2048 but after change in my.cnf and restart mariadb I got this errors on aria tables: #138 - ...
1
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1answer
79 views

Where Mysqldump gets data from

How mysqldump is processing backup? From which all files is it reads data for creating dump? Is the process differs if storage engines are different?
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2answers
1k views

Inserting into mysql table with archive engine “duplicate key” error

I am trying to archive some files using mysql archive engine. I am using this query to insert file contents: insert into test_table (id,arch) values (123,'FILE_CONTENT') After inserting 2 records, ...
2
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1answer
748 views

TokuDB database size unknown in phpmyadmin

In mysql server, I installed the TokuDB storage engine. I converted database engine InnoDB to TokuDB, but my table sizes show unknown in phpmyadmin.
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1answer
1k views

How to convert innodb engine tables to tokudb engine

Hi I want to migarate my server newly installed tokudb engine. i want to convert each table of database from innodb to tokudb. How can I do that using sed command ?
3
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2answers
1k views

Question about non-clustered index storage in SQL Server

I have a table people with two non-clustered indexes. create table people( id_person int, first_name varchar(50), last_name varchar(50), city varchar(100), state char(2), zip_code int ) CREATE ...
0
votes
1answer
767 views

Mysql federated engine table creation error

I am trying to create a federated table on my local machine which suppose to connect to my another machine which also in my local network. I have enabled federated engine on both machines and is shown ...
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1answer
1k views

Unknown storage engine 'XtraDB'

I installed Percona Server 5.6.12-rc60.4, when I want create table such as : CREATE TABLE IF NOT EXISTS `mydb`.`table` ( `id` INT NOT NULL AUTO_INCREMENT , `title` VARCHAR( 64 ) NOT NULL , PRIMARY ...
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2answers
207 views

Which MySQL engine should i use where most operations are read operations

I want to develop an application for which i will need a database to store data. I am using MySQL as backend. My question is Which MySQL engine should i use? Well, i have mentioned some important ...
1
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1answer
733 views

Does SQL Server check disk space before allocating a new page?

I have a bet with my old boss. I bet her that SQL Server, when allocating a new extent, always allocates from the buffer pool and never checks to see whether there is some place on disk where the ...
2
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1answer
493 views

Issues converting MyISAM table to InnoDB (auto column issue)

I'm having issues trying to convert a table from MyISAM to InnoDB in MySQL 5.6. The following is the table dump: -- -- Table structure for table `companies` -- DROP TABLE IF EXISTS `companies`; /*!...
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1answer
543 views

Is there a query to set a table's engine to innodb if it's not already?

I can set a (MyISAM) table's engine to InnoDB using the query: alter table tablename engine=InnoDB which takes some time to complete for large tables. It appears though that if I run the same query ...
1
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1answer
137 views

Issue with Storage Engine

Just got the below error in one of the slave. I just Googled it and changed the variable myisam_data_pointer_size from 4 to 6. Somehow, my ALTER TABLE was successful. Can you please let me know ...
2
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1answer
435 views

Is the Memory engine adequate for a read intensive/lookup table?

I have an InnoDB table with just two columns, a VARCHAR(20) and a DATETIME, and around 4M rows. This table serves as a blacklist for other tables, and is truncated and recreated from a csv file from ...
3
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1answer
469 views

Which MySQL table to use for read-only, bulk-loaded tables?

So I have a workload on 2 key tables in my application with the following characteristics: READ-ONLY DATA The data is bulk-loaded in a fully consistent manner from a single process on a schedule, ...
1
vote
1answer
600 views

Can I use symlink or data directory for ARCHIVE MySQL tables?

All mention of either using a symlink or data/index separate data directories state that MyISAM is the only supported (https://dev.mysql.com/doc/refman/5.5/en/symbolic-links.html). However, I found ...
0
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2answers
426 views

Best MySQL storage engine for read heavy table with two indexes

I have a pretty big MySQL table (70G) with about 15 columns and 1.5M rows. There is one index on the autoincrement id and one on a foreign key (integer). Apart from that there are several VARCHAR and ...
5
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1answer
274 views

Which MySQL storage engine is the most similar to ARCHIVE when that is not available?

I have a table that contains a log of events that is written to often and read very infrequently by comparison. I would love to use the ARCHIVE engine, because it is basically designed for exactly ...
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3answers
3k views

Is MariaDB a suitable drop in replacement for MySQL on a standard LAMP stack?

I've been wondering lately what (if any) are the improvements available in MariaDB over 'conventional' MySQL? I understand that where platform interoperability and/or backwards compatibility may be ...
1
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1answer
504 views

What storage engine should I use for this MySQL table?

I have a table where I store all the urls from my website, and I update them from time to time when a visitor enters. The primary key is the url itself varchar(255). I have set it to use InnoDB but ...
6
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1answer
7k views

Do you still use MyISAM or prefer Aria storage engine?

If Aria storage engine (previously called Maria) is the "new" MyISAM, which supports transaction and automatic crash recovery: Why still use MyISAM ? Should changing storage engine from MyISAM to ...
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4answers
73k views

Which is faster, InnoDB or MyISAM?

How can MyISAM be "faster" than InnoDB if MyISAM needs to do disk reads for the data? InnoDB uses the buffer pool for indexes and data, and MyISAM just for the index?
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1answer
2k views

Which mysql storage engine to choose?

I'm confused about which mysql engine should I choose (lets talk about the most used : MyISAM and InnoDB). The theories say: Both work with BTree indexes, but MyISAM can work with FULLTEXT index ...
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2answers
1k views

How is it possible for mysql storage engine to be NULL?

I'm just reading a book and in one of the examples I get notices: That the engine in the information_schema.table is null, how is that possible? Can I create tables without any engine??, is there ...
12
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1answer
938 views

Slot Array and Total Page Size

I continue to read in many forums and on many blogs that a page is comprised as shown below: Page Size: 16 x 512B = 8192B Page Header: = 96B Maximum In_Row Row: = 8060B This leaves (...