I have my MySQL server running with 4 databases and innodb_data_file_path set to the default configuration[ibdata1]. I see the size of this file on disk growing as big as 1GB. This file will only grow as the application that runs this server is collecting the monitoring data.
Just not sure how this will have performance issue with such a large file size.
Is there a way to split this file per database? so that each database can have its own ibdata file. I know InnoDB has an option where this data file can be split per table (still maintaining a shared tablespace), but could not find any option to split this file per database.
Can someone please help me out here?
Add this option to my.cnf : *innodb_file_per_table*
Reference :
http://dev.mysql.com/doc/refman/5.0/en/innodb-multiple-tablespaces.html
There should be a separate tablespace file per database already. You should see an ibdata file in each subdirectory for the different databases in the mysql data directory.
Related
Say my website takes in lots of data from its users, and it goes to MySQL on my computer, but my computer runs out of space. If I connect a hard drive to my server computer, can I make it so I can put a new database on that hard drive, and all the data gets stored there? It would obviously be attached at all times.
This probably belongs on https://dba.stackexchange.com/ instead, and indeed there's quite a bit of in-depth discussion there about some of the techniques you could use.
One thing I've found helpful when working with large but temporary datasets is to enable innodb_file_per_table which — in my case — helps reclaim disk space when removing these temporary databases.
Moving the entire datadir
You can move the entire directory that MySQL uses to store files; this is called the datadir. Stop the MySQL daemon, move the folder, edit my.cnf to refer datadir = to the new folder location, and start the daemon.
File-per-table tablespace outside of the datadir
https://dev.mysql.com/doc/refman/5.6/en/tablespace-placing.html
You can use the file-per-table tablespace configuration (innodb_file_per_table in the [mysqld] portion of the configuration file) in conjunction with CREATE TABLE to actually place a tablespace outside the datadir. When you have innodb_file_per_table enabled, you can use statements like CREATE TABLE t1 (c1 INT PRIMARY KEY) DATA DIRECTORY = '/alternative/directory'; to put the datadir for that tablespace in a different directory.
Partitioning
Using partitioning, you can break up the databases, tables, and columns in to different storage partitions. This is probably not what you're looking for in this case because they still reside in the datadir. https://dev.mysql.com/doc/refman/5.7/en/partitioning.html
You can export the database via PhpMyAdmin and the pass the saved database file onto another computer.
Exporting the database:
https://serverpilot.io/community/articles/how-to-export-a-database-using-phpmyadmin.html
Importing the database:
https://serverpilot.io/community/articles/how-to-import-a-database-using-phpmyadmin.html
I am attempting to restore my old databases to a new Wamp installation. However, I did not take a backup of Mysql files before I did this. Thankfully the uninstallation has not deleted all the files, but in my data folder I have :
1) All the databases (As folders)
2) auto.cnf
There are no ib* files in the old folder. Is it still possible to restore my databases somehow?
I have tried to replace the entire mysql5.6.17 folder (there has been no change of version between the installations), but Wamp remains orange and never turns green.
If I replace only the data folder, the MySQL service starts, I can see the databases, but not the tables.
If I change the path in my.ini to point to the old wamp's data folder, I cannot see the old databases at all.
EDIT : Was experimenting a bit, copying the database folders directly into the new Wamp's data folder allows me to get a list of all the tables properly, but there is no actual data in the tables, and trying to query it using MySQLWorkbench gives me the error :
Error Code: 1146. Table 'testdb.users' doesn't exist
EDIT 2 : Found this in the error log file in my data folder :
2014-08-03 06:24:46 25164 [Warning] InnoDB: Cannot open table testdb/users from the internal data dictionary of InnoDB though the .frm file for the table exists. See http://dev.mysql.com/doc/refman/5.6/en/innodb-troubleshooting.html for how you can resolve the problem.
As I thought, its a problem with InnoDB's own mapping. Is there a way to resolve this manually?
If you created an INNODB database, and made no other config changes to store the actual data in seperate table spaces then all the actual data for that INNODB databases will have been stored in the \wamp\bin\mysql\mysql5.6.17\ibdata1 file.
If you do not have that file from the old install then your data is lost.
There will also be info in a \wamp\bin\mysql\mysql5.6.17\data\DATA_BASE_NAME\ folder, one .frm file for each table that was in the database, but this is basically just schema information and not actual data.
For future reference, InnoDB Backup and Recovery
GOLDEN RULE:
Always backup database (from phpmyadmin) before major changes.. better to spend 1 minute for that, than going into trouble..
How to Copy data folder
If you want to copy the database, then INSTALLATION/mysql versions should be same.. then rename newly installed data folder to i.e. data_my_old,so now there you can place the backuped data folder (it should contain ibdata1 file).
Depends on innodb_file_per_table setting.
If it was OFF then all your tables were in ibdata1. Now you have quite new ibdata1 (since you see errors "Cannot open table testdb/users from the internal data dictionary", that means InnoDB runs fresh new dictionary). That means that now the data is somewhere on the disk. The recovery is quite difficult and requires a lot of tedious work. You need to take an image of the disk, scan it with stream_parser to find InnoDB pages, then recover the InnoDB dictionary, then find index_id of every table and if the stream_parser has found this index run c_parser to extract records from the index.
If innodb_file_per_table was ON and you do see .ibd files in the databases directories then recovery is much easier. First, you may try to reconnect individual ibd files with ibdconnect or extract records from the ibd files with stream_parser/c_parser.
The mentioned tools are part of TwinDB data recovery toolkit
i have just done a google search and found this....
Go to C:\wamp\bin\mysql\mysql5.5.24\data
Find a file called "mysql-bin.index"
Rename that file to "mysql-bin.index-corrupt"
Restart the server and it will work fine, all your database will be where you left them.
By some reason these files ibdata1, ib_logfile0, ib_logfile1 were been deleted from hard drive, mysql server was restarted and of course one of the database stoped with error "db.table does not exist!". Is it possible to restore somehow these files, if there are only *.frm, db.opt files?
Thanks.
Take disk image as soon as possible or mount MySQL partition read-only(if it was not on /).
Then you need to compile data recovery toolkit(install dependencies if "make" fails):
make
Then scan the disk image with page_parser. It will find InnoDB pages and sort them per page type, per index_id.
./page_parser -f /path/to/disk.img
Then you need table structures (either take them from old backup or restore from .frm). You need the structure to compile constraints_parser - a tool that fetches records from InnoDB page(s).
./constraints_parser -5f pages-XXXXXX/FIL_PAGE_INDEX/0-x/
Save output in some file. It will also generate LOAD DATA to stderr to upload the dump back to MySQL.
Check the documentation on Percona's website for more details.
From my experience, 70-80%% of data should be recoverable after this kind of accident.
I want to purge the ibdata1, ib_logfile0 and ib_logfile1 files in MySQL. Because these files are taking too much space of my C:\ disk. And I don't want to move these files anywhere else in the Hard disk. I heard about purging which can shrink the data. I am using Windows Vista. What are the steps to be done to purge the data ?
The log files can be removed anytime. Only the most recent log is kept open/locked. However, deleting id_data will trash all of your InnoDB databases - that's the actual data store.
As pointed out by MarcB, you can delete the (old) logfiles without problems; MySQL does not need them to run.
The data file ibdata* must not be deleted, it contains the actual database data.
I will grow as the database grows; unfortunately there is not way to shrink it, even if you later delete data from the database. The only way is to dump and reimport the whole database.
Also see this question: MySQL data file won't shrink
It explains various options to better cope with growing data files.
Short answer: There's no way to reduce the size of the ibdata files once they grew to a certain size. MySQL recommends dumping all innodb type data, shutting down mysql, deleting the ibdata files and restarting, then loading the data again. A one-click "compact" solution like other systems have is still missing.
I have to restore a database that has been inadvertently DROPped in MySQL 5.0. From checking the backup files, I only seem to have .FRM files to hold the database data.
Can anyone advise whether this is all I need to perform a database restore/import from the backup, or are there other files I should have to hand to complete this?
.frm files are not the data files, they just store the "data dictionary information" (see MySQL manual). InnoDB stores its data in ib_logfile* files. That's what you need in order to do a backup/restore. For more details see here.
Restoring innodb:
(assuming your data folder is C:\ProgramData\MySQL\MySQL Server 5.5\data)
Copy the folders of the databases (named after the database name) you want to restore to C:\ProgramData\MySQL\MySQL Server 5.5\data
Copy the 3 ibdata files to the data folder ex. (C:\ProgramData\MySQL\MySQL Server 5.5\data)
_ib_logfile0
_ib_logfile1
_ibdata1
Get the size of the _ib_logfile0 in MB (it should be the same as _ib_logfile1) by File Right click -> Properties
Edit the mysql config file (mysql\bin\my.ini) for the innodb_log_file_size=343M to be exactly the ibdata files size
Run
mysqld --defaults-file=mysql\bin\my.ini --standalone --console
--innodb_force_recovery=6
Now your data should be back in your database. Export them using phpmysql or any other tool
The detailed solution you can found here:
http://www.unilogica.com/mysql-innodb-recovery/ (Article in Portuguese)
Besides the flag of innodb_force_recovery, I found another solution: innodb_file_per_table, that splits InnoDB tables in each file like MyISAM tables.
In a crash recovery you can lost less data than in single file ibdata1.