How to migrate large mysql database where remote server has stringent limits? - mysql

I have a local database thats about 1GB and my remote host is a free host that I am using for testing. want to make sure everything works before i spend money on a paid host. The problem is the phpmyadmin on the remote server only allows 50mb files which which just doesn't cut it, especially since the restore usually fails due to execution time limits. Below is the list of everything I've tried.
LOCAL
phpmyadmin -----> backingup of table no longer work because of timeout even with modified php.ini settings because of shear size of db
mysqldumper -----> program creates dumps with inserts, there is no option for me to make it create insert ignores. ill explain the problem later below.
mysqlworkbench -----> creates database using database name of my local server (problem is my remote server has a different database name and i cant open a 1gb .sql file to edit the database name at the very top. computer just craps out and I have to force quit workbench)
sqlsplitter (mac program) cuts up large .sql or .sql.gz files
REMOTE
phpmyadmin with .gz/.sql files cut up into 20mb chunks
-----> timeout. phpmyadmin resume function doesnt work either. it just overwrites old data
mysqldumper -----> process ends up in an error randomly midway through my restore on remote server using a backup created with mysqldumper on my local computer (single file or multipart, both dont work). could be at 10% completion, could be at 50%.
bigdump -----> used single and multipart dumps from mysqldumper, same problem. randomly quits halfway through. some multiparts were successful in completing, but when one failed and I tried the failed part again, it would give me an error saying unique key already exists in table. i dont want to unset all my unique key stuff and have to go through and delete all duplicates later.
mysqldumper -----> does not work with dump from mysqlworkbench
bigdump -----> gives me an error sql error denied for creating database using dump from mysqlworkbench (i cannot open up a 1 gb file to delete that 1 line that says create database)
Does anybody know of a better method to upload to my host? I have no command line access on there and only a 500mb space limit (no limit on sql space though).
Thanks

Use mysqldump. Figure out what the error you're seeing is, and fix it. The mysqldump utility works. I've restored dumpfiles with hundreds of gigabytes of data to servers, and never use anything else. If it doesn't work for you, you're doing something incorrectly.
You can prevent it from writing a USE database-name; statement at the top of the file by invoking it with the database name as the last argument, without using the --databases option before it.
You can add the --insert-ignore command line option to write all the INSERT statements as INSERT IGNORE to work around your partial insert issues
You can use --no-data to extract a dump file that contains table definitions, not data, and get all of the tables declared, first.
You can use the --no-create-info option to extract a dump file with just the inserts, not the table definitions.
http://dev.mysql.com/doc/refman/5.6/en/mysqldump.html
You can also use a simple bash loop to extract each table into its own file, so you have smaller files to work with:
for TABLE in `mysql [args] -e 'show tables in database-name'`; do mysqldump [args] database-name $TABLE > $TABLE.sql; done
When restoring the files, add the --compress option to the mysql command line arguments for a faster transfer, and specify your (new) database name as the last argument, so the client will use the correct database before applying the file, which no longer contains the database name.

Related

Some file lost in MySQL database. How to re-create it in proper way?

The problem is, that one MYI and one MYD file from MySQL database has been accidentally deleted. The only file left intact is FRM one. Only one table from the whole database is damaged that way, all other tables are OK and the database works generally fine, except the table with deleted files, which is obviously inaccessible.
There's a full database dump in pure SQL format available.
The question is, how do I re-create these files and table in safe and proper manner?
My first idea was to extract the full create table command from the dump and run it on live database. It's not so easy, as the whole dump file has over 10GB, so any operations within its content are really pain in . Yes, I know about sed and know how to use it - but I consider it the last option to choose.
Second and current idea is to create copy of this database on independent server, make a dump of the table in question and then use resulting SQL file to create the table again on the production server. I'm not quite experienced with MySQL administration tasks (well, just basic ones), but for me this option seems to be safe and reasonable.
Will the second option work as I expect?
Is it the best option, or are there any more recommendable solutions?
Thank you in advance for your help.
The simplest solution is to copy the table you deleted. There's a chance mysqld still has an open file handle to the data files you deleted. On UNIX/Linux/OS X, a file isn't truly deleted while some process still has an open file handle to it.
So you might be able to do this:
mysql> CREATE TABLE mytable_copy LIKE mytable;
mysql> INSERT INTO mytable_copy SELECT * FROM mytable;
If you've restarted MySQL Server since you deleted the files, this won't work. If the server has closed its file handle to the data file, this won't work. If you're on Windows, I have no idea.
The next simplest solution is to restore your existing 10GB dump file to a temporary instance of MySQL Server, as you said. I'd use MySQL Sandbox but some people would use a virtual machine, or if you're using an AWS environment, launch a spot EC2 instance or a small RDS instance.
Then dump just the table you need:
mysqldump -h tempserver mydatabase mytable > mytable.sql
Then restore it to your real server.
mysql -h realserver mydatabase < mytable.sql
(I'm omitting the user & password options, I prefer to put those in .my.cnf anyway)

Importing 200k table [duplicate]

During development, how our local WAMP servers get up-to-date data from the test server is that a dump of the database is made and we upload that dump using the source command to load the .sql file.
Recently, at the very end of the import we have been getting errors about the #old variables which stored the original settings like foreign key constraints before they’re changed (so turning off foreign key constraints so that the import doesn’t throw errors when it recreates tables and attempts to create foreign keys when one of the tables has yet to be created). I have worked out that the cause is that the product table is getting more and more data and at a point the session has timed out during the import.
I’m wondering what setting can I set (either as part of the SQL query on in the my.ini file) that will stop all timeouts, in effect making a session last forever while we are signed in.
Strategies for importing large MySQL databases
PHPMyAdmin Import
Chances are if you’re reading this, PHPMyAdmin was not an option for your large MySQL database import. Nonetheless it is always worth a try, right? The most common cause of failure for PHPMyAdmin imports is exceeding the import limit. If you’re working locally or have your own server, you can try changing the MySQL ini settings usually found in the my.ini file located in the MySQL install folder. If you’re working with WAMP on Windows, you can access that file using the WAMP control panel under MySQL > my.ini. Remember to restart WAMP so your new settings will be used. Settings you may want to increase here include:
max_allowed_packet
read_buffer_size
Even with enhanced MySQL import settings you may still find that imports time out due to PHP settings. If you have access to PHP.ini, you can make edits to the maximum execution time and related settings. In WAMP, access the PHP.ini file under the WAMP control panel at PHP > php.ini. Consider raising the limits on the following settings while trying large MySQL imports:
max_execution_time
max_input_time
memory_limit
Using Big Dump staggered MySQL dump importer
If basic PHPMyAdmin importing does not work, you may want to try the Big Dump script from Ozerov.de for staggered MySQL imports. What this useful script does is run your import in smaller blocks, which is exactly what is often needed to successfully import a large MySQL dump. It is a free download available at http://www.ozerov.de/bigdump/.
The process of using Big Dump is fairly simple: you basically position your SQL import file and the Big Dump script together on the server, set a few configs in the Big Dump script and then run the script. Big Dump handles the rest!
One key point about this otherwise great option, is that it will not work at all on MySQL exports that contain extended inserts. So if you have the option to prevent extended inserts, try it. Otherwise you will have to use another method for importing your large MySQL file.
Go command line with MySQL console
If you’re running WAMP (and even if you’re not) there is always the option to cut to the chase and import your large MySQL database using the MySQL console. I’m importing a 4GB database this way as I write this post. Which is actually why I have some time to spend writing, because even this method takes time when you have a 4GB SQL file to import!
Some developers (usually me) are intimidated by opening up a black screen and typing cryptic commands into it. But it can be liberating, and when it comes to MySQL databases it often the best route to take. In WAMP we access the MySQL console from the WAMP control panel at MySQL > MySQL Console. Now let’s learn the 2 simple MySQL Console commands you need to import a MySQL database, command-line style:
use `db_name`
Command use followed by the database name will tell the MySQL console which database you want to use. If you have already set up the database to which you are importing, then you start by issuing the use command. Suppose your database is named my_great_database. In this case, issue the following command in the MySQL Console. Note that commands must end with a semi-colon.
mysql-> use my_great_database;
mysql-> source sql_import_file.sql
Command source followed by the location of a SQL file will import the SQL file to the database you previously specified with the use command. You must provide the path, so if you’re using WAMP on your local server, start by putting the SQL file somewhere easy to get at such as C:\sql\my_import.sql. The full command with this example path would be:
mysql-> source C:\sql\my_import.sql;
After you run that command, the SQL file should begin to be imported. Let the queries run and allow the import to complete before closing the MySQL console.
Further documentation for MySQL command line can be found here: http://dev.mysql.com/doc/refman/5.5/en/mysql.html.
Another solution is to use MySQL Workbench.
This solution worked for me:
max_allowed_packet <-- --> upped size to 8M
read_buffer_size <-- --> upped from 256 to 512
Using Xampp control panel on localhost. After making the changes to the my.ini file in MySQL config, don’t forget to quit Xampp (or Wamp) and restart it for changes to take effect.
(Four days of head-banging and I finally got it fixed!)
Symptoms were on Import: #2006 MySql server went away. However, only 10 table rows were being imported out of 87 table rows.
Consider using MySQL Workbench, it's free and handles very large script very well (from the menu choose: File -> Open SQL Script - if it's large, it will ask you if you'd like run it). Has served me well over the years when working with large SQL dumps.

export mysql database schema and data using phpmyadmin

I'm trying to export a database with phpmyadmin but the result is a file that can't be read. In phpmyadmin I leave the options and only add compression. After downloading I'm unable to open the resulted .sql file (after extracting) in geany and get a complaint about the file being in an encoding that's not supported. Every time I do the export the file seems to be of a random size as if the process just stops somewhere.
It's a small database with joomla stuff that needs to be moved to another site and I would like to use mysldump but don't have ssh access. Other than the phpmyadmin in the cpanel I can't think of another way to access that data but phpmyadmin doesn't seem to be up for doing the job.
Is there any setting I should have to have a look at or some other way to get that data exported?
Try disabling compression or using another compression method. There have been a few bugs in phpMyAdmin. Maybe you are stumbling about one of them. Also try opening the sql file in an ordinary text editor and check the content maybe you can get some more information about the problem you are experiencing.
If you have access to the commandline you can also try the following command: mysqldump -u <username> -p <database_name> > dumpfilename.sql.

How to Prevent Connection Timeouts for Large MySQL Imports

During development, how our local WAMP servers get up-to-date data from the test server is that a dump of the database is made and we upload that dump using the source command to load the .sql file.
Recently, at the very end of the import we have been getting errors about the #old variables which stored the original settings like foreign key constraints before they’re changed (so turning off foreign key constraints so that the import doesn’t throw errors when it recreates tables and attempts to create foreign keys when one of the tables has yet to be created). I have worked out that the cause is that the product table is getting more and more data and at a point the session has timed out during the import.
I’m wondering what setting can I set (either as part of the SQL query on in the my.ini file) that will stop all timeouts, in effect making a session last forever while we are signed in.
Strategies for importing large MySQL databases
PHPMyAdmin Import
Chances are if you’re reading this, PHPMyAdmin was not an option for your large MySQL database import. Nonetheless it is always worth a try, right? The most common cause of failure for PHPMyAdmin imports is exceeding the import limit. If you’re working locally or have your own server, you can try changing the MySQL ini settings usually found in the my.ini file located in the MySQL install folder. If you’re working with WAMP on Windows, you can access that file using the WAMP control panel under MySQL > my.ini. Remember to restart WAMP so your new settings will be used. Settings you may want to increase here include:
max_allowed_packet
read_buffer_size
Even with enhanced MySQL import settings you may still find that imports time out due to PHP settings. If you have access to PHP.ini, you can make edits to the maximum execution time and related settings. In WAMP, access the PHP.ini file under the WAMP control panel at PHP > php.ini. Consider raising the limits on the following settings while trying large MySQL imports:
max_execution_time
max_input_time
memory_limit
Using Big Dump staggered MySQL dump importer
If basic PHPMyAdmin importing does not work, you may want to try the Big Dump script from Ozerov.de for staggered MySQL imports. What this useful script does is run your import in smaller blocks, which is exactly what is often needed to successfully import a large MySQL dump. It is a free download available at http://www.ozerov.de/bigdump/.
The process of using Big Dump is fairly simple: you basically position your SQL import file and the Big Dump script together on the server, set a few configs in the Big Dump script and then run the script. Big Dump handles the rest!
One key point about this otherwise great option, is that it will not work at all on MySQL exports that contain extended inserts. So if you have the option to prevent extended inserts, try it. Otherwise you will have to use another method for importing your large MySQL file.
Go command line with MySQL console
If you’re running WAMP (and even if you’re not) there is always the option to cut to the chase and import your large MySQL database using the MySQL console. I’m importing a 4GB database this way as I write this post. Which is actually why I have some time to spend writing, because even this method takes time when you have a 4GB SQL file to import!
Some developers (usually me) are intimidated by opening up a black screen and typing cryptic commands into it. But it can be liberating, and when it comes to MySQL databases it often the best route to take. In WAMP we access the MySQL console from the WAMP control panel at MySQL > MySQL Console. Now let’s learn the 2 simple MySQL Console commands you need to import a MySQL database, command-line style:
use `db_name`
Command use followed by the database name will tell the MySQL console which database you want to use. If you have already set up the database to which you are importing, then you start by issuing the use command. Suppose your database is named my_great_database. In this case, issue the following command in the MySQL Console. Note that commands must end with a semi-colon.
mysql-> use my_great_database;
mysql-> source sql_import_file.sql
Command source followed by the location of a SQL file will import the SQL file to the database you previously specified with the use command. You must provide the path, so if you’re using WAMP on your local server, start by putting the SQL file somewhere easy to get at such as C:\sql\my_import.sql. The full command with this example path would be:
mysql-> source C:\sql\my_import.sql;
After you run that command, the SQL file should begin to be imported. Let the queries run and allow the import to complete before closing the MySQL console.
Further documentation for MySQL command line can be found here: http://dev.mysql.com/doc/refman/5.5/en/mysql.html.
Another solution is to use MySQL Workbench.
This solution worked for me:
max_allowed_packet <-- --> upped size to 8M
read_buffer_size <-- --> upped from 256 to 512
Using Xampp control panel on localhost. After making the changes to the my.ini file in MySQL config, don’t forget to quit Xampp (or Wamp) and restart it for changes to take effect.
(Four days of head-banging and I finally got it fixed!)
Symptoms were on Import: #2006 MySql server went away. However, only 10 table rows were being imported out of 87 table rows.
Consider using MySQL Workbench, it's free and handles very large script very well (from the menu choose: File -> Open SQL Script - if it's large, it will ask you if you'd like run it). Has served me well over the years when working with large SQL dumps.

Import a large database - CPanel & MySQL & PHPMyAdmin

I have a database which has the size over 100 MB. It has the .sql.gz which means it is compressed. When I try to import it using PHPMyAdmin I get time out errors. I even tried partial imports ( Allow the interruption of an import in case the script detects it is close to the PHP timeout limit. (This might be good way to import large files, however it can break transactions.) ) which does not work for me. Given that I'm using CPanel & PHPMyAdmin to get the job done.
How can import this database?
You can use BigDump for this
Adjust the database configuration and charset in this file
Remove the old tables on the target database if your dump doesn't contain "DROP TABLE"
Create the working directory (e.g. dump) on your web server
Upload bigdump.php and your dump files (.sql, .gz) via FTP to the working directory
Run the bigdump.php from your browser via URL like
http://www.yourdomain.com/dump/bigdump.php
BigDump can start the next import session automatically if you enable the JavaScript
Wait for the script to finish, do not close the browser window
IMPORTANT: Remove bigdump.php and your dump files from the web server
If Timeout errors still occure you may need to adjust the $linepersession setting in this file. Read more
Very Simple and Effective Technique to import large mysql databases.
Using Command Line console
you can access command line using putty for server and execute following command
mysql -u 'database_user' -p'database_password' database_name < sql_file_name_with_full_path
Using Cron Job [if console is not available]
add a cron job in cpanel with following command
mysql -u 'database_user' -p'database_password' database_name < sql_file_name_with_full_path
Do not forget to delete cron job after importing database. Also delete sql file from server.
for both techniques commands are same
Example
mysql -u 'test_user' -p'123456' test_db < /home1/test/public_html/db.sql
or if you do not have password
mysql -u 'test_user' test_db < /home1/test/public_html/db.sql
In my opinion and experience with hepsiawebhosting.com server, it's better and faster to set those parameters under WHM settings called "Tweak setting". Under Tweak settings you can modify maximum upload and maximum post, and you can could, for example, change upload to 120 MiB and post to 125 MiB.
Also, in PHP settings under WHM, you can change the default socket and SQL time out. You need to increase those settings.
You can also unzip the database and try to upload it as a simple .sql file.
I hope this will help you.
why this is not published, what is missing here?