0
votes
0answers
14 views

MariaDB Galera setup with drastically different amounts of memory used on cluster nodes - why?

We have a 3 node MariaDB Galera cluster. All nodes are identical and the config on each is identical. They have 64GB of RAM each. The output of the following query is 28: SELECT ...
0
votes
2answers
32 views

Fastest way to create local copy of live InnoDB MySQL database?

We have a MySQL database (InnoDB) on our live Ubuntu 12.04 server which has grown quite large (25gb+). Every month or so we need to copy this database to our development machines to work on locally. ...
-2
votes
1answer
25 views

How does InnoDB store tables in ibdata file? [on hold]

There are two tables and their default engine is InnoDB. I want know the following What's inside the ibdata file ? How does InnoDB store these two tables ?
0
votes
1answer
35 views

How can i import 150GB database after deleting ibdata1,logfile in MYSQL?

I have 150GB database and my ibdata1 file size is 240GB so i want shrink the ibdata1 file so for that i have to export the DB and then drop the tables and then stop mysql, delete the ibdata1 file and ...
0
votes
0answers
17 views

using Aria vs InnoDB vs MyISAM

I was wondering (if anyone knows) if Aria database is crash safe . I had some tables with MyISAM which were getting corrupted very often and switch them to InnoDB . However innodb is a bit slower and ...
1
vote
0answers
17 views

Move all InnoDB databases into one subdirectory (innodb_file_per_table is ON)

First of all, excuse my English. I want to run a MySQL 5.6 on ZFS volume, and need to move all InnoDB databases to one subdirectory (which in fact will be a different ZFS filesystem). For example, by ...
0
votes
1answer
86 views
+50

MySQL - Best long read query solution within a replication based system

I'm working on a project where work in a queue requires a database read against heterogeneous table schemas (InnoDB/MyISAM). The queries constructed during the "read" process can result in 10-15 ...
-1
votes
2answers
53 views

When do I need transactions /locks?

I know that transactions are meant to group several operations as one. But if for example in the same table one transaction does DELETE FROM table where state = 'done' and another does either SELECT ...
1
vote
0answers
23 views

What do spikes in InnoDB lock structures indicate?

I co-maintain a high traffic site similar to StackExchange. It runs MySQL 5.1 (working on replacing it with MySQL 5.5 or MariaDB). All our tables are InnoDB. MySQL goes down a couple of times a day. ...
0
votes
3answers
41 views

How to repair, or drop/create a corrupted table in mysql?

Situation: I have a MySQL database with 104 tables, running locally on XAMPP on windows 7. All the tables have InnoDB engine. XAMPP MySQL is running as windows service. As front end I have PHP ...
1
vote
2answers
31 views

Is there a rule of thumb regarding the size and number of a buffer pool instances?

I know the consensus seems to be approximately 75% of ram should be dedicated to the buffer pool. But, I'm more interested in the optimal number of buffer pool instances. What are some things to ...
0
votes
1answer
30 views

Restore InnoDB from .frm files

My database crashed and my PC and I now only have the .frm and .ibd files left. Is there any way to restore my database?
0
votes
1answer
63 views

Delete Query takes a long time

I have a innodb table that counts circa 1 billion entries. I started a delete operation (with a small where condition on an indexed column) that should delete a lot entries, leaving circa 100 million. ...
0
votes
1answer
38 views

mysql directory grow to 246G after one query, which failed due to table is full

I was trying to run the following statement with the hope to create a join of two existing tables. create table CRS_PAIR select concat_ws(',', a.TESTING_ID, b.TRAINING_ID, a.TESTING_C) as k, ...
0
votes
0answers
22 views

Converting UUID's from CHAR(32) to BIN(16)

I have a few questions relating to UUID's, but before I go on, let me explain our schema a bit, first, we're on MySQL 5.5 (Percona's version to be exact)... In each applicable table, we use a two ...
1
vote
1answer
40 views

MySQL not releasing memory

MySQL seems to want to keep an entire table in cache (table size = ~20GB) after any large inserts or select statements are performed on it. Right now my innodb buffer pool is 20GB. Total RAM is 32GB. ...
1
vote
1answer
42 views

Innodb buffer pool and multiple joins

assume we have 1 Billion records and want to store them in One or Three tables by post_type. post_id -> primary key post_type -> ( page, group, user ) user_id -> index date -> ...
0
votes
1answer
44 views

Slow queries with many self joins in variable-column database

I'm creating a table structure which needs to handle a variable number of columns. To handle that case the table structure is a listing of cells with a column and row number. To view the table a ...
1
vote
0answers
37 views

RDS MYSQL instance rebooted and won't load INNODB table

So my production db in RDS apparently either crashed or was rebooted during a version update, and upon being restarted mysql couldn't load one of the innodb tables: as evidenced by the following error ...
0
votes
2answers
49 views

Can CPU cores be separated for MySQL?

Is it possible to separate CPU cores in Mysql? I understand it is possible for Memory as we can tune it in innodb_buffer_pool_size or innodb_additional_mem_pool_size. How about CPU cores in ...
1
vote
1answer
44 views

MySQL 5.1: Upgrade innodb plugin

My application is running on MySQL 5.1.58 community edition. As I studied on SO websites that After acquisition by Oracle, new InnoDB plugin has been released and MySQL 5.1 with InnoDB plugin is the ...
0
votes
0answers
18 views

MariaDB : Larger innodb_buffer_pool_size causing SQL updates to be slower

Has anyone here encountered such scenario before where and update statement took longer time to run when innodb_buffer_pool_size is bigger. I've run a few tests using the same statements on around ...
0
votes
1answer
20 views

Immigrate to file-per-table mode in MySQL

I have 20 MySQL databases and in each there are about 20 tables. All the data is saved in a file called ibData1. Now I discovered about the file per table mode but if I change the value in the my.ini ...
1
vote
1answer
22 views

creating table result in errno 150

I'm trying to create the following schema, but I'm getting errors when I'm trying to create project and staffphone tables. Not sure what is it complaining about. mysql> CREATE TABLE staff( ...
2
votes
2answers
27 views

Mysql used key changes between two consecutive EXPLAINs

I have a huge unmaintained innodb table (~1.5billion rows), I just started to try to query it. I write && instead of AND once; and surprise! it uses different key! EXPLAIN EXTENDED SELECT * ...
1
vote
1answer
45 views

Migrate from innodb_file_per_table to off in MySQL

We have a large number (2,500+) of databases and users in MySQL 5.6 on a single virtualized server (4 cpus and 8GB of memory). All the tables are using InnoDB. The actual data size is not very large ...
1
vote
1answer
36 views

mariadb 5.5.36 with innodb plugin

I installed mariadb 5.5.36 on a win32 system. Everything runs fine except innodb requests are 2 x slower than an identical MySQL installation. So I want to switch back to original innodb plugin to ...
3
votes
1answer
53 views

MySQL runs out of memory when importing innodb database

I have a small VPS with 512MB RAM and no swap (can't have any). I am importing a 1.5GB innodb database with mysql -u -p < database.sql Before the operation can finish it says : Lost connection ...
3
votes
1answer
18 views

Is the innodb_lazy_drop_table problem solved?

I'm researching database configuration for MySQL/MariaDB. I've been reading the configuration chapter in "High Performance MySQL". In there, it suggests that innodb_lazy_drop_table can be used to ...
0
votes
2answers
40 views

Recovering mysql innodb table from table.ibd backup file

Just practising DB disaster recovery. As per our back up policy, we do complete disk image back ups every half an hour (on our slave server). Now for a scenario, where some how a table has been ...
1
vote
3answers
58 views

Verify mysqldump backup is corruption free

We've got a cron task backing up our Database using mysqldump - my main concern is corruption, short of manually importing and checking the backups each time whats the best way to check / verify a ...
1
vote
2answers
52 views

Transaction basics. What is the result of 2 transactions running concurrently?

I have a rather basic question on transactions. Assume a table Account with a column amount. Now we have the following code: BEGIN $amount = SELECT amount FROM ACCOUNT WHERE id = 123; $amount = ...
0
votes
1answer
39 views

Why is setting open_files_limit making MySQL slow?

We noticed that adding open_files_limit in /etc/my.cnf is making server slow. Reference : What variable(s) to look to maintain MySQL speed of scanning through all database tables while it starts?
0
votes
1answer
40 views

ib_logfile0 and ib_logfile1 got deleted

After restoring from a percona-xtrabackup without a preparation step, ib_logfile0 and ib_logfile1 were not present in the restore data. Therefor during startup the following message is observed: ...
1
vote
1answer
64 views

Why does auto increment jumps by more than the number of rows inserted?

I am very perturbed by this weird behaviour I am seeing in the auto_increment value recorded in the bidID of a Bids table after performing bulk insertion using a stored procedure: INSERT INTO Bids ...
0
votes
3answers
87 views

What does “InnoDB stores its tables and indexes in a tablespace” mean?

Was reading the mysql engine innoDB tutorial, I came across this sentence "InnoDB stores its tables and indexes in a tablespace" Can any body explain me this what does it means. Thank you :)
0
votes
1answer
46 views

Is there a table size above which SELECT performance degrades significantly?

In MySQL, does SELECT performance degrade significantly after a certain table size? I have a table with about 107 million rows and some queries seem stuck in "Sending data" for a long time. Of course, ...
0
votes
2answers
62 views

What variable(s) to look to maintain MySQL speed of scanning through all database tables while it starts?

We have few thousand small databases with total .ibd files of about 800000. We noticed that MySQL takes couple of minutes to stop but about two hours to start. For e.g. while MySQL is starting and ...
0
votes
1answer
37 views

The most efficient method to obtain the total entries into a mysql table

I have a table that has a very high usage (insert/update/select) - one of the operations is to obtain a count of the number of rows. So far I've been using the classic select count(pk) from table but ...
0
votes
1answer
50 views

how to recover .ibd and .frm files in mysql

so i am developing java application with mysql 5.6.13, few days before i purchased new laptop, from previous laptop i forgot to create dump of application instead i copied folder of my database(.ibd ...
0
votes
1answer
23 views

Check whether MySQL Innodb Rows are compressed

After setting the various variables to enable compression on the Innodb Barracuda tables, what query will you use to check that those tables are indeed compressed?
0
votes
1answer
52 views

Error 1005: Can't create table can't find where the problem is

I have created a EER model using MySQL Workbench (latest release). Apparently all is fine but when I try to do a FORWARD ENGINEER I get the common Error 1005: Can't create table. As suggested in this ...
-1
votes
1answer
15 views

Mysql InnoDB exsited but can't show it

I have a InnoDB table A , While I type "show tables" , I can't see it. Even I type "drop table A" , it responses "table doesn't exist" . While I create a table B which refers from A , table B can ...
1
vote
1answer
39 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 ...
1
vote
1answer
98 views

Compressing Base64 Encoded Image in Database Field. Table Size too Large

Database Info Database Type - Percona MySQL. Table engine - InnoDB. I have a database table that is currently using 17GB at 400,000 rows. This size is mainly because I'm storing a 40kb base64 ...
1
vote
1answer
45 views

Error while importing sql - Specified key was too long; max key length is 1000 bytes

I am trying to import an sql file which shows me the following error: Error SQL query: -- -------------------------------------------------------- -- -- Table structure for table `users` -- CREATE ...
1
vote
1answer
54 views

MyISAM with Innodb in the same Wordpress database reduce performace?

My new Wordpress database all the Wordpress created tables use InnoDB engine and plugin created table use MyISAM. But older site database all the tables use MyISAM table engine. I use MySQL ...
0
votes
0answers
22 views

row locking with innodb [duplicate]

What is the most efficient way to lock a specific row for within a mysql transaction. I am currently using for update using select is there another method that im unaware of? if not are mysql locks ...
1
vote
1answer
21 views

mysql multiple database prioritize innodb buffer pool size

With a mysql instance and multiple databases within that instance is there a way to allocate which database you would like to assign priority to the buffer pool size?
0
votes
0answers
19 views

Temporary table created on disk, with 14mb of database

i have only one database (on one machine) with size 14 mb for temporary table i have this configration max_heap_table_size= 1000M tmp_table_size= 1000M sort_buffer_size=4M join_buffer_size=4M i ...