Restore the mysql database from .frm files

Question

I have dumped all my tables everyweek to got the backup. But later I understand that it is only storing the .frm file of the table. It is not showing .MYD and .MYI files of a table. So I have only my .frm file of the database with me and also mydatabase is innodb. So can I get my database with data in the database?

Answer 1

Yes this is possible. It is not enough you just copy the .frm files to the to the databse folder but you also need to copy the ib_logfiles and ibdata file into your data folder. I have just copy the .frm files and copy those files and just restart the server and my database is restored.

After copying the above files execute the following command -

sudo chown -R mysql:mysql /var/lib/mysql

The above command will change the file owner under mysql and it's folder to MySql user. Which is important for mysql to read the .frm and ibdata files.

Answer 2

Just might be useful for someone:

I could only recover frm files after a disaster, at least I could get the table structure from FRM files by doing the following:

1- create some dummy tables with at least one column and SAME NAME with frm files in a new mysql database.

2-stop mysql service

3- copy and paste the old frm files to newly created table's frm files, it should ask you if you want to overwrite or not for each. replace all.

4-start mysql service, and you have your table structure...

regards. anybudy

Answer 3

I answered this question here, as well: https://dba.stackexchange.com/a/42932/24122

I recently experienced this same issue. I'm on a Mac and so I used MAMP in order to restore the Database to a point where I could export it in a MySQL dump.

You can read the full blog post about it here: http://www.quora.com/Jordan-Ryan/Web-Dev/How-to-Recover-innoDB-MySQL-files-using-MAMP-on-a-Mac

You must have:

-ibdata1

-ib_logfile0

-ib_logfile1

-.FRM files from your mysql_database folder

-Fresh installation of MAMP / MAMP Pro that you are willing to destroy (if need be)

1. SSH into your web server (dev, production, no difference) and browse to your mysql folder (mine was at /var/lib/mysql for a Plesk installation on Linux)
2. Compress the mysql folder
3. Download an archive of mysql folder which should contain all mySQL databases, whether MyISAM or innoDB (you can scp this file, or move this to a downloadable directory, if need be)
4. Install MAMP (Mac, Apache, MySQL, PHP)
5. Browse to /Applications/MAMP/db/mysql/
6. Backup /Applications/MAMP/db/mysql to a zip archive (just in case)

7. Copy in all folders and files included in the archive of the mysql folder from the production server (mt Plesk environment in my case) EXCEPT DO NOT OVERWRITE:

   -/Applications/MAMP/db/mysql/mysql/

   -/Applications/MAMP/db/mysql/mysql_upgrade_info

   -/Applications/MAMP/db/mysql/performance_schema

8. And voila, you now should be able to access the databases from phpMyAdmin, what a relief!

But we're not done, you now need to perform a mysqldump in order to restore these files to your production environment, and the phpmyadmin interface times out for large databases. Follow the steps here:

http://nickhardeman.com/308/export-import-large-database-using-mamp-with-terminal/

Copied below for reference. Note that on a default MAMP installation, the password is "root".

How to run mysqldump for MAMP using Terminal

EXPORT DATABASE FROM MAMP[1]

Step One: Open a new terminal window

Step Two: Navigate to the MAMP install by entering the following line in terminal cd /applications/MAMP/library/bin Hit the enter key

Step Three: Write the dump command ./mysqldump -u [USERNAME] -p [DATA_BASENAME] > [PATH_TO_FILE] Hit the enter key

Example:

./mysqldump -u root -p wp_database > /Applications/MAMP/htdocs/symposium10_wp/wp_db_onezero.sql

Quick tip: to navigate to a folder quickly you can drag the folder into the terminal window and it will write the location of the folder. It was a great day when someone showed me this.

Step Four: This line of text should appear after you hit enter Enter password: So guess what, type your password, keep in mind that the letters will not appear, but they are there Hit the enter key

Step Five: Check the location of where you stored your file, if it is there, SUCCESS Now you can import the database, which will be outlined next.

Now that you have an export of your mysql database you can import it on the production environment.

Answer 4

I made use of mysqlfrm which is a great tool which generates table creation sql code from .frm files. I was getting this nasty table not found error although tables were being listed. Thus I used this tool to regenerate the tables. In ubuntu you need to install this as:

sudo apt install mysql-utilities

then,

mysqlfrm --diagnostic mysql/db_name/ > db_name.sql

Create a new database and then you can use,

mysql -u username -p < db_name.sql

However, this will give you the tables but not the data. In my case this was enough.

Answer 5

Yes! It is possible

Long approach but you can get all the data's using just .frm files. Of course, you need other files in the mysql/data directory.

My Problem

One day my hard disk crashed and got the booting blue screen error. I try connecting with multiple machines and it didn't work. Since it is a booting error I was concerned about the files. and I tried with the secondary hard disk and try to recover the folders and files. I also backed up the full xampp folder c:/xampp just in case, Because I had no back of the recent databases I got really worried about how to retrieve the database. we have a lot of clients' project management and personal doc in the database.

None of the methods listed on the StackOverflow comment works, at least for me. It took me 2 full days googling for the answer to getting the data from the .frm files. Came across multiple approaches from many people but everything was frustrating and getting some error or another when implementing. If most of them get it working (based on their comment) then what am I missing.

Because I was so desperate I even reinstall windows which result in losing all my software and tried again. But still the same error

THANKS to Dustin Davis

I found the solution in his blog and I managed to get it working exactly the same way he did. Let me give the credit to this guy, Dustin Davis (https://dustindavis.me/restoring-mysql-innodb-files-on-windows/). You could jump from here to his blog and try his method, pretty clear and easy to follow.

But there is something I discovered when trying his approach that he hasn't explained in his blog and I will try my best to explain how I did and what you need to look for.

Follow this exactly

IMPORTANT: Make sure you install the same version of XAMPP. You cannot copy-paste from older XAMPP to a new version. This will result in __config or __tracking errors.

How to check your XAMPP version

1. Go to your xampp folder (you're backed up xampp).
2. Open the readme_en.txt file. which is in the root directory of the xampp.
3. You should see the version on top. ###### ApacheFriends XAMPP Version X.X.XX ######

Files require to restore

xampp(old folder)/mysql/data/

ibdata1
ib_logfile0
ib_logfile1
<databasename>/*.frm
<databasename>/*.ibd

Step 1

1. After installing the same version of xampp.
2. Do not start the apache or myql

Step 2

• Go to the mysql/data folder and replace the ibdata1, ib_logfile0, and ib_logfile1
• Now copy paste your database folder from your old xampp backup to the newly installed xampp folder c:/xampp/mysql/data/ that contain .frm and .ibd files, If you are not sure try with one database.

Step 3

• Go to c:/xampp/mysql/bin and look for my.cn.
• Open the my.cn file and look for #skip-innodb and under that look for the line that says innodb_log_file_size=5M change it to 170M. innodb_log_file_size=170M. This is your log file size and if you are not sure just set it to 170

Step 4

• Now open the file mysql_start.bat (Windows Batch file) that is in the c:/xampp/ directory.

• Add –innodb_force_recovery=6 after the ... --console

   ....
  
   mysql\bin\mysqld --defaults-file=mysql\bin\my.ini --standalone --console -–innodb_force_recovery=6
   if errorlevel 1 goto error
   goto finish
  

Step 5

• Now Start your Apache and Mysql.
• Go to your PHPMyAdmin and check for your database and its tables. if you do not get any errors you are on the right track.
• Stop the Apache and Mysql and copy-paste the rest of the databases.

Answer 6

I just copy pasted the database folders to data folder in MySQL, i.e. If you have a database called alto then find the folder alto in your MySQL -> Data folder in your backup and copy the entire alto folder and past it to newly installed MySQL -> data folder, restart the MySQL and this works perfect.

Answer 7

Copy all file and replace to /var/lib/mysql , after that you must change owner of files to mysql this is so important if mariadb.service restart has been faild

chown -R mysql:mysql /var/lib/mysql/*

and

chmod -R 700 /var/lib/mysql/*

Answer 8

After much trial and error I was able to get this working based on user359187 answer and this blog post.

To get my old .frm and .ibd transferred to a new MySQL database after copying the files over and assigning MySQL ownership, the key for me was to then log into MySQL and connect to the new database then let MySQL do the work by importing the tablespace.

mysql> connect test;
mysql> ALTER TABLE t1 IMPORT TABLESPACE;

This will import the data using the copied .frm and .ibd files.

I had to run the Alter command for each table separately but this worked and I was able to recover the tables and data.

Answer 9

Before starting you should stop the WAMP services, or at least restart the services when prompted to start them.

On the old server instance navigate to the MySQL data folder by default this should look something similar to C:\wamp\bin\mysql\mysql5.1.53\data\ where mysql5.1.53 will be the version number of the previously installed MySQL database.

Inside this folder you should see a few files and folders. The folders are the actual MySQL databases, and contain a bunch of .frm files which we will require. You should recognise the folder names as the database names. These folder and all their contents can be copied directly to your MySQL data folder, you can neglect the default databases mysql, performance_schema, test.

If you started the server now you will see the databases are picked up, however the databases will contain none of the tables which were copied across. In order for the contents of the database to be picked up, back in the data folder you should see a file ibdata1, this is the data file for tables, copy this directly into the data folder, you should already have a file in your new data folder called “ibdata1″ so you may wish to rename this to ibdata1.bak before copying across the ibdata1 from the old MySQL data folder.

Once this has been done Restart all the WAMP services. You can use PhpMyAdmin to check if your databases have been successfully restored.

Answer 10

create a new database with same name copy the .frm .ibd files into xampp/mysql/data/[databasename]/

you will need ibdata file as well which is found inside

xampp/mysql/data/ copy the previous ibdata1 file paste in the paste the file and replace it with the existing ibdata file

[caution: you may loose the contents of the database which are newly created in the new ibdata file]