Why phpMyAdmin does not import light file? [duplicate] - mysql

I am trying to import a large .sql data file using phpMyAdmin in XAMPP. However this is taking a lot of time and I keep getting:
Fatal error: Maximum execution time of 300 seconds exceeded in C:\xampp\phpMyAdmin\libraries\dbi\DBIMysqli.class.php on line 285
And the file is about 1.2 million lines long.
The file is about 30MB big, so it is not that big. I don't really understand why it is taking so long.
;;;;;;;;;;;;;;;;;;;
; Resource Limits ;
;;;;;;;;;;;;;;;;;;;
; Maximum execution time of each script, in seconds
; http://php.net/max-execution-time
; Note: This directive is hardcoded to 0 for the CLI SAPI
max_execution_time=30000
; Maximum amount of time each script may spend parsing request data. It's a good
; idea to limit this time on productions servers in order to eliminate unexpectedly
; long running scripts.
; Note: This directive is hardcoded to -1 for the CLI SAPI
; Default Value: -1 (Unlimited)
; Development Value: 60 (60 seconds)
; Production Value: 60 (60 seconds)
; http://php.net/max-input-time
max_input_time=60
; Maximum input variable nesting level
; http://php.net/max-input-nesting-level
;max_input_nesting_level = 64
; How many GET/POST/COOKIE input variables may be accepted
; max_input_vars = 1000
; Maximum amount of memory a script may consume (128MB)
; http://php.net/memory-limit
memory_limit=200M
The is the config file for php.ini in xampp, for some reason i still get
Fatal error: Maximum execution time of 300 seconds exceeded in C:\xampp\phpMyAdmin\libraries\dbi\DBIMysqli.class.php on line 285.

There's a configuration variable within the phpMyAdmin directory that you can find in libraries\config.default.php called $cfg['ExecTimeLimit'] that you can set to whatever maximum execution time you need.

Well, to get rid of this you need to set phpMyadmin variable to either 0 that is unlimited or whichever value in seconds you find suitable for your needs. Or you could always use CLI(command line interface) to not even get such errors(For which you would like to take a look at this link.
Now about the error here, first on the safe side make sure you have set PHP parameters properly so that you can upload large files and can use maximum execution time from that end. If not, go ahead and set below three parameters from php.ini file,
max_execution_time=3000000 (Set this as per your req)
post_max_size=4096M
upload_max_filesize=4096M
Once that's done get back to finding phpMyadmin config file named something like "config.default.php". On XAMPP you will find it under "C:\xampp\phpMyAdmin\libraries" folder. Open the file called config.default.php and set :
$cfg['ExecTimeLimit'] = 0;
Once set, restart your MySQL and Apache and go import your database.
Enjoy... :)

Set Only 3 Parameters from php.ini file of your server
A. max_execution_time = 3000000 (Set as per your requirment)
B. post_max_size = 4096M
C. upload_max_filesize = 4096M
Edit C:\xampp\phpMyAdmin\libraries\config.default.php Page
$cfg['ExecTimeLimit'] = 0;
After all set, restart your server and import again your database.
Done

You're trying to import a huge dataset via a web interface.
By default PHP scripts run in the context of a web server have a maximum execution time limit because you don't want a single errant PHP script tying up the entire server and causing a denial of service.
For that reason your import is failing. PHPMyAdmin is a web application and is hitting the limit imposed by PHP.
You could try raising the limit but that limit exists for a good reason so that's not advisable. Running a script that is going to take a very long time to execute in a web server is a very bad idea.
PHPMyAdmin isn't really intended for heavy duty jobs like this, it's meant for day to day housekeeping tasks and troubleshooting.
Your best option is to use the proper tools for the job, such as the mysql commandline tools. Assuming your file is an SQL dump then you can try running the following from the commandline:
mysql -u(your user name here) -p(your password here) -h(your sql server name here) (db name here) < /path/to/your/sql/dump.sql
Or if you aren't comfortable with commandline tools then something like SQLYog (for Windows), Sequel Pro (for Mac), etc may be more suitable for running an import job

This worked for me.
If you got Maximum execution time 300 exceeded in DBIMysqli.class.php file. Open the following file in text editor
C:\xampp\phpMyAdmin\libraries\config.default.php then
search the following line of code:
$cfg[‘ExecTimeLimit’] = 300;
and change value 300 to 900.
https://surya2in1.wordpress.com/2015/07/28/fatal-error-maximum-execution-time-of-300-seconds-exceeded/

Simply set $cfg['ExecTimeLimit'] = 0; In xampp/phpMyAdmin/libraries/config.default.php.
Maximum execution time in seconds (0 for no limit).
And make this below changes in php.ini file as per file size.
post_max_size = 600M
upload_max_filesize = 500M
max_execution_time = 5000
max_input_time = 5000
memory_limit = 600M
But make sure 'post_max_size' and 'memory_limit' should be more than upload_max_filesize.
**Note - Don't forget to restart your server.

If you are using the laragon and your database is phpMyAdmin the process is the same for tackle this error.
Open laragon right-click on it and open php.ini file
set these value accordingly to your needs
max_execution_time
post_max_size
upload_max_filesize
Open new file config.default.php
path is C:\laragon\etc\apps\phpMyAdmin\libraries\config.default.php
and set the value of this $cfg['ExecTimeLimit'] = 0;
Restart the laragon.
I hope it would solve your problem for laragon environment 🙏 #Happy Coding :)

Is it a .sql file or is it compressed (.zip, .gz, etc)? Compressed formats sometimes require more PHP resources so you could try uncompressing it before uploading.
However, there are other methods you can try also. If you have command-line access, just upload the file and import with the command line client mysql (once at the mysql> prompt, use databasename; then source file.sql).
Otherwise you can use the phpMyAdmin "UploadDir" feature to put the file on the server and have it appear within phpMyAdmin without having to also upload it from your local machine.
This link has information on using UploadDir and this one has some more tips and methods.

you must change php_admin_value max_execution_time in your Alias config (\XAMPP\alias\phpmyadmin.conf)
answer is here:
WAMPServer phpMyadmin Maximum execution time of 360 seconds exceeded

After trying many things with no success, I've managed to get SSH access to the server, and import my 80Mb database with a command line, instead of phpMyAdmin. Here is the command:
mysql -u root -p -D mydatabase -o < mydatabase.sql
It's much easier to import big databases, if you are running xammp on windows, the path for mysql.exe is C:\xampp\mysql\bin\mysql.exe

1-make a search in your local drive and type "php.ini"
2-you may see many files named php.ini you should choose the one that fits with your php version (see localhost)
3-open the php.ini file make a search on "max_execution_time" then make it equal to "-1" to make it unlimited

Never change original config.default.php file.
Changing general executing time in php.ini has no effect on phpmyadmin scripts.
Use a new config.inc.php or the config.sample.inc.php provided in the /phpMyAdmin folder instead.
You can set $cfg[‘ExecTimeLimit’] = 0; means endless execution in the config.inc.php as recommended above. Be aware this is not a "normal" ini file. Its a php script, so you need a open <?php at the beginning of that file.
But most important: Do not use this procedure at all! phpmyadmin is okay for small database but not for huge databases with several MB or GB.
You have other tools on a server to handle the import.
a) If you have a server admin
system like Plesk, use there database import tool.
b) use ssh commands to make database dump or to write databases directly in
mysql via ssh. Commands below.
Create a database dump:
mysqldump DBname --add-drop-table -h DBhostname -u DBusername -pPASSWORD > databasefile.sql
Write a database to mysql:
mysql -h rdbms -u DBusername -pPASSWORD DBname < databasefile.sql

Best solution for this error when i tried some points.
Follow this steps to solve this issue:
locate the file [XAMPP Installation Directory]\php\php.ini (e.g. C:\xampp\php\php.ini)
open php.ini in Notepad or any Text editor
locate the line containing max_execution_time and
increase the value from 30 to some larger number (e.g. set: max_execution_time = 90)
then restart Apache web server from the XAMPP control panel

Changing the max_execution_timeout in php.ini. may help with maximum execution error. but sometimes the database is imported correctly but still it shows maximum execution time error, it can be due to some error of xamp.
I was experiencing the same error even after making all changes in php.ini. which is mentioned above and realized that all the things, tables of database were imported and it was working fine but it was still showing the max_execution_timeout error.

Set Only 3 Parameters from php.ini file of your server
A. max_execution_time = 3000000 (Set as per your requirment)
B. post_max_size = 4096M
C. upload_max_filesize = 4096M
Case 1 : If you are Using Xampp, Edit
C:\xampp\phpMyAdmin\libraries\config.default.php
Case 2 : If you are Using Wampp, Edit
c:\wamp64\apps\phpMyAdmin\libraries\config.default.php
Case 3 : If you are Using Laragon, Edit
C:\laragon\etc\apps\phpMyAdmin\libraries\config.default.php
search for $cfg['ExecTimeLimit'] in config.default.php file and make the following changes
$cfg['ExecTimeLimit'] = 0;
After all set, restart your server and import again your database.
Done

You can increase the limit:
ini_set('max_execution_time', 3000);
(Note that this script can cause high memory usage as well, so you probably have to increase that as well)
Other possible solution: Chunk your sql file, and process it as parts. I assume, it is not one big SQL query, is it?
Update: As #Isaac pointed out, this is about PHPMyAdmin. In this case set max_execution_timeout in php.ini. (The location depends on your environment)

The following might help you:
ini_set('max_execution_time', 100000);
And in your mysql - max_allowed_packet=100M in some cases where queries are too long sql also produce and error "MySQL server has gone away";
Change the values to whatever you need.

Related

MySQL error "Got a packet bigger than 'max_allowed_packet' bytes"

I'm trying to import a table from an sql dump with a size of 4.7G which includes longblobs using the following command:
mysql --max-allowed-packet=2048M -uroot -p otobo < /backup/article_data_mime_plain.sql
even though the option "--max-allowed-packet" it's usually more then enough when set to "512M" in this particular case not even 2G which is the allowed limit seems to be usefull at all giving the following output:
ERROR 1153 (08S01) at line 2270: Got a packet bigger than 'max_allowed_packet' bytes
Thanks in advance, any suggestion is welcome.
Here are the steps to do this:
Open the MySQL configuration file (my.cnf or my.ini)
Find the [mysqld] section and add the following line:
max_allowed_packet=64M
Save the file and restart the MySQL server for the changes to take effect.
Note: You should set the "max_allowed_packet" value to a value that is appropriate for your use case, taking into consideration the available system memory and other requirements.
It's also a good idea to increase the value of the net_buffer_length configuration variable on the client, as it can affect the size of the packets being transmitted during the dump process. The default value is 16384 bytes. For example:
[mysql]
net_buffer_length=128K
Once you have made the changes, you can retry the database dump and it should complete successfully.

MySql execution timeout

I have a local LAMP server on my machine with phpmyadmin also installed.
I am trying to run a Levenstein distance calculator between expressions with known spelling and ones with possible spelling errors. The 300K misspelled stack is being checked against 1.5M correct ones. The program runs fine and does what it has to do but stops at 60 seconds.
I did try to change the execution time as:
SET SESSION MAX_EXECUTION_TIME=20000;
SET GLOBAL MAX_EXECUTION_TIME=20000;
SET GLOBAL connect_timeout=28800
SET GLOBAL wait_timeout=28800
SET GLOBAL interactive_timeout=28800
with no improvement. The I changed the php.ini as:
max_execution_time = 300
max_input_time = 600
and restarted the server. Still no change.
Can somebody advise me how I can have the script run for a couple of hours on my local machine. Thanks.
I figured it out. It was the php that timed out. I added the following to my script:
set_time_limit(3000);
and now it runs for as long as I want it to. :)

mysql chef database recipe fails on large file

"MySQL server has gone away". Hmm.
I am using vagrant and chef to setup my virtual development environment. I'm almost there, but on the last step chef fails when attempting to execute my external db_setup.sql file. I can execute this same script by SSH'ing into the virtual server and it installs without difficulty.
This is my problem code (in cookbooks/database/recipies/mysql.rb file):
# Query a database from a sql script on disk
mysql_database 'run script' do
database_name 'my_db'
connection mysql_connection_info
retries 3
sql { ::File.open('/vagrant/db_setup.sql').read }
action :query
end
The file is 6.9mb and the error I receive when I run vagrant provision is:
==> default: [2014-08-24T16:04:53-07:00] ERROR: mysql_database[run script]
(database::mysql line 50) had an error: Mysql::Error: MySQL server has gone away
For what it's worth, when I replace the db_setup.sql file with a smaller, simpler file that just creates a few empty tables, it executes without difficulty.
Any suggestions? Thank you in advance!
Many, many things can cause this error. In my experience it's usually an SQL file of over 1MB, or, the wait_timeout in your servers my.cnf is set very low (sixty seconds) needs properly tuned. When deploying my.cnf try a wait_timeout 86400 and a max_allowed_packet of "enough" to import that file.
For example:
[mysqld]
wait_timeout = 86400
max_allowed_packet = 1GB
PS. I would not recommend this high of parameters in actual production.
I worked around this issue by getting Chef to leverage the mysql command line tool instead of using Ruby to read the .sql file.

Intermittent mySQL crash. phpmyadmin logs me out when I click on variables tab [duplicate]

I'm running a server at my office to process some files and report the results to a remote MySQL server.
The files processing takes some time and the process dies halfway through with the following error:
2006, MySQL server has gone away
I've heard about the MySQL setting, wait_timeout, but do I need to change that on the server at my office or the remote MySQL server?
I have encountered this a number of times and I've normally found the answer to be a very low default setting of max_allowed_packet.
Raising it in /etc/my.cnf (under [mysqld]) to 8 or 16M usually fixes it. (The default in MySql 5.7 is 4194304, which is 4MB.)
[mysqld]
max_allowed_packet=16M
Note: Just create the line if it does not exist
Note: This can be set on your server as it's running.
Note: On Windows you may need to save your my.ini or my.cnf file with ANSI not UTF-8 encoding.
Use set global max_allowed_packet=104857600. This sets it to 100MB.
I had the same problem but changeing max_allowed_packet in the my.ini/my.cnf file under [mysqld] made the trick.
add a line
max_allowed_packet=500M
now restart the MySQL service once you are done.
I used following command in MySQL command-line to restore a MySQL database which size more than 7GB, and it works.
set global max_allowed_packet=268435456;
It may be easier to check if the connection exists and re-establish it if needed.
See PHP:mysqli_ping for info on that.
There are several causes for this error.
MySQL/MariaDB related:
wait_timeout - Time in seconds that the server waits for a connection to become active before closing it.
interactive_timeout - Time in seconds that the server waits for an interactive connection.
max_allowed_packet - Maximum size in bytes of a packet or a generated/intermediate string. Set as large as the largest BLOB, in multiples of 1024.
Example of my.cnf:
[mysqld]
# 8 hours
wait_timeout = 28800
# 8 hours
interactive_timeout = 28800
max_allowed_packet = 256M
Server related:
Your server has full memory - check info about RAM with free -h
Framework related:
Check settings of your framework. Django for example use CONN_MAX_AGE (see docs)
How to debug it:
Check values of MySQL/MariaDB variables.
with sql: SHOW VARIABLES LIKE '%time%';
command line: mysqladmin variables
Turn on verbosity for errors:
MariaDB: log_warnings = 4
MySQL: log_error_verbosity = 3
Check docs for more info about the error
Error: 2006 (CR_SERVER_GONE_ERROR)
Message: MySQL server has gone away
Generally you can retry connecting and then doing the query again to solve this problem - try like 3-4 times before completely giving up.
I'll assuming you are using PDO. If so then you would catch the PDO Exception, increment a counter and then try again if the counter is under a threshold.
If you have a query that is causing a timeout you can set this variable by executing:
SET ##GLOBAL.wait_timeout=300;
SET ##LOCAL.wait_timeout=300; -- OR current session only
Where 300 is the number of seconds you think the maximum time the query could take.
Further information on how to deal with Mysql connection issues.
EDIT: Two other settings you may want to also use is net_write_timeout and net_read_timeout.
In MAMP (non-pro version) I added
--max_allowed_packet=268435456
to ...\MAMP\bin\startMysql.sh
Credits and more details here
If you are using xampp server :
Go to xampp -> mysql -> bin -> my.ini
Change below parameter :
max_allowed_packet = 500M
innodb_log_file_size = 128M
This helped me a lot :)
This error is occur due to expire of wait_timeout .
Just go to mysql server check its wait_timeout :
mysql> SHOW VARIABLES LIKE 'wait_timeout'
mysql> set global wait_timeout = 600 # 10 minute or maximum wait time
out you need
http://sggoyal.blogspot.in/2015/01/2006-mysql-server-has-gone-away.html
I was getting this same error on my DigitalOcean Ubuntu server.
I tried changing the max_allowed_packet and the wait_timeout settings but neither of them fixed it.
It turns out that my server was out of RAM. I added a 1GB swap file and that fixed my problem.
Check your memory with free -h to see if that's what's causing it.
On windows those guys using xampp should use this path xampp/mysql/bin/my.ini and change max_allowed_packet(under section[mysqld])to your choice size.
e.g
max_allowed_packet=8M
Again on php.ini(xampp/php/php.ini) change upload_max_filesize the choice size.
e.g
upload_max_filesize=8M
Gave me a headache for sometime till i discovered this. Hope it helps.
It was RAM problem for me.
I was having the same problem even on a server with 12 CPU cores and 32 GB RAM. I researched more and tried to free up RAM. Here is the command I used on Ubuntu 14.04 to free up RAM:
sync && echo 3 | sudo tee /proc/sys/vm/drop_caches
And, it fixed everything. I have set it under cron to run every hour.
crontab -e
0 * * * * bash /root/ram.sh;
And, you can use this command to check how much free RAM available:
free -h
And, you will get something like this:
total used free shared buffers cached
Mem: 31G 12G 18G 59M 1.9G 973M
-/+ buffers/cache: 9.9G 21G
Swap: 8.0G 368M 7.6G
In my case it was low value of open_files_limit variable, which blocked the access of mysqld to data files.
I checked it with :
mysql> SHOW VARIABLES LIKE 'open%';
+------------------+-------+
| Variable_name | Value |
+------------------+-------+
| open_files_limit | 1185 |
+------------------+-------+
1 row in set (0.00 sec)
After I changed the variable to big value, our server was alive again :
[mysqld]
open_files_limit = 100000
This generally indicates MySQL server connectivity issues or timeouts.
Can generally be solved by changing wait_timeout and max_allowed_packet in my.cnf or similar.
I would suggest these values:
wait_timeout = 28800
max_allowed_packet = 8M
If you are using the 64Bit WAMPSERVER, please search for multiple occurrences of max_allowed_packet because WAMP uses the value set under [wampmysqld64] and not the value set under [mysqldump], which for me was the issue, I was updating the wrong one. Set this to something like max_allowed_packet = 64M.
Hopefully this helps other Wampserver-users out there.
There is an easier way if you are using XAMPP.
Open the XAMPP control panel, and click on the config button in mysql section.
Now click on the my.ini and it will open in the editor. Update the max_allowed_packet to your required size.
Then restart the mysql service. Click on stop on the Mysql service click start again. Wait for a few minutes.
Then try to run your Mysql query again. Hope it will work.
It's always a good idea to check the logs of the Mysql server, for the reason why it went away.
It will tell you.
MAMP 5.3, you will not find my.cnf and adding them does not work as that max_allowed_packet is stored in variables.
One solution can be:
Go to http://localhost/phpmyadmin
Go to SQL tab
Run SHOW VARIABLES and check the values, if it is small then run with big values
Run the following query, it set max_allowed_packet to 7gb:
set global max_allowed_packet=268435456;
For some, you may need to increase the following values as well:
set global wait_timeout = 600;
set innodb_log_file_size =268435456;
For Vagrant Box, make sure you allocate enough memory to the box
config.vm.provider "virtualbox" do |vb|
vb.memory = "4096"
end
This might be a problem of your .sql file size.
If you are using xampp. Go to the xampp control panel -> Click MySql config -> Open my.ini.
Increase the packet size.
max_allowed_packet = 2M -> 10M
The unlikely scenario is you have a firewall between the client and the server that forces TCP reset into the connection.
I had that issue, and I found our corporate F5 firewall was configured to terminate inactive sessions that are idle for more than 5 mins.
Once again, this is the unlikely scenario.
uncomment the ligne below in your my.ini/my.cnf, this will split your large file into smaller portion
# binary logging format - mixed recommended
# binlog_format=mixed
TO
# binary logging format - mixed recommended
binlog_format=mixed
I found the solution to "#2006 - MySQL server has gone away" this error.
Solution is just you have to check two files
config.inc.php
config.sample.inc.php
Path of these files in windows is
C:\wamp64\apps\phpmyadmin4.6.4
In these two files the value of this:
$cfg['Servers'][$i]['host']must be 'localhost' .
In my case it was:
$cfg['Servers'][$i]['host'] = '127.0.0.1';
change it to:
"$cfg['Servers'][$i]['host']" = 'localhost';
Make sure in both:
config.inc.php
config.sample.inc.php files it must be 'localhost'.
And last set:
$cfg['Servers'][$i]['AllowNoPassword'] = true;
Then restart Wampserver.
To change phpmyadmin user name and password
You can directly change the user name and password of phpmyadmin through config.inc.php file
These two lines
$cfg['Servers'][$i]['user'] = 'root';
$cfg['Servers'][$i]['password'] = '';
Here you can give new user name and password.
After changes save the file and restart WAMP server.
I got Error 2006 message in different MySQL clients software on my Ubuntu desktop. It turned out that my JDBC driver version was too old.
I had the same problem in docker adding below setting in docker-compose.yml:
db:
image: mysql:8.0
command: --wait_timeout=800 --max_allowed_packet=256M --character-set-server=utf8 --collation-server=utf8_general_ci --default-authentication-plugin=mysql_native_password
volumes:
- ./docker/mysql/data:/var/lib/mysql
- ./docker/mysql/dump:/docker-entrypoint-initdb.d
ports:
- 3306:3306
environment:
MYSQL_ROOT_PASSWORD: ${MYSQL_ROOT_PASSWORD}
MYSQL_DATABASE: ${MYSQL_DATABASE}
MYSQL_USER: ${MYSQL_USER}
MYSQL_PASSWORD: ${MYSQL_PASSWORD}
I also encountered this error. But even with the increased max_allowed_packet or any increase of value in the my.cnf, the error still persists.
What I did is I troubleshoot my database:
I checked the tables where the error persists
Then I checked each row
There are rows that are okay to fetch and there are rows where the error only shows up
It seems that there are value in these rows that is causing this error
But even by selecting only the primary column, the error still shows up (SELECT primary_id FROM table)
The solution that I thought of is to reimport the database. Good thing is I have a backup of this database. But I only dropped the problematic table, then import my backup of this table. That solved my problem.
My takeaway of this problem:
Always have a backup of your database. Either manually or thru CRON job
I noticed that there are special characters in the affected rows. So when I recovered the table, I immediately changed the collation of this table from latin1_swedish_ci to utf8_general_ci
My database was working fine before then my system suddenly encountered this problem. Maybe it also has something to do with the upgrade of the MySQL database by our hosting provider. So frequent backup is a must!
Just in case this helps anyone:
I got this error when I opened and closed connections in a function which would be called from several parts of the application.
We got too many connections so we thought it might be a good idea to reuse the existing connection or throw it away and make a new one like so:
public static function getConnection($database, $host, $user, $password){
if (!self::$instance) {
return self::newConnection($database, $host, $user, $password);
} elseif ($database . $host . $user != self::$connectionDetails) {
self::$instance->query('KILL CONNECTION_ID()');
self::$instance = null;
return self::newConnection($database, $host, $user, $password);
}
return self::$instance;
}
Well turns out we've been a little too thorough with the killing and so the processes doing important things on the old connection could never finish their business.
So we dropped these lines
self::$instance->query('KILL CONNECTION_ID()');
self::$instance = null;
and as the hardware and setup of the machine allows it we increased the number of allowed connections on the server by adding
max_connections = 500
to our configuration file. This fixed our problem for now and we learned something about killing mysql connections.
For users using XAMPP, there are 2 max_allowed_packet parameters in C:\xampp\mysql\bin\my.ini.
This error happens basically for two reasons.
You have a too low RAM.
The database connection is closed when you try to connect.
You can try this code below.
# Simplification to execute an SQL string of getting a data from the database
def get(self, sql_string, sql_vars=(), debug_sql=0):
try:
self.cursor.execute(sql_string, sql_vars)
return self.cursor.fetchall()
except (AttributeError, MySQLdb.OperationalError):
self.__init__()
self.cursor.execute(sql_string, sql_vars)
return self.cursor.fetchall()
It mitigates the error whatever the reason behind it, especially for the second reason.
If it's caused by low RAM, you either have to raise database connection efficiency from the code, from the database configuration, or simply raise the RAM.
For me it helped to fix one's innodb table's corrupted index tree. I localized such a table by this command
mysqlcheck -uroot --databases databaseName
result
mysqlcheck: Got error: 2013: Lost connection to MySQL server during query when executing 'CHECK TABLE ...
as followed I was able to see only from the mysqld logs /var/log/mysqld.log which table was causing troubles.
FIL_PAGE_PREV links 2021-08-25T14:05:22.182328Z 2 [ERROR] InnoDB: Corruption of an index tree: table `database`.`tableName` index `PRIMARY`, father ptr page no 1592, child page no 1234'
The mysqlcheck command did not fix it, but helped to unveil it.
Ultimately I fixed it as followed by a regular mysql command from a mysql cli
OPTIMIZE table theCorruptedTableNameMentionedAboveInTheMysqld.log

MySQL error 2006: mysql server has gone away

I'm running a server at my office to process some files and report the results to a remote MySQL server.
The files processing takes some time and the process dies halfway through with the following error:
2006, MySQL server has gone away
I've heard about the MySQL setting, wait_timeout, but do I need to change that on the server at my office or the remote MySQL server?
I have encountered this a number of times and I've normally found the answer to be a very low default setting of max_allowed_packet.
Raising it in /etc/my.cnf (under [mysqld]) to 8 or 16M usually fixes it. (The default in MySql 5.7 is 4194304, which is 4MB.)
[mysqld]
max_allowed_packet=16M
Note: Just create the line if it does not exist
Note: This can be set on your server as it's running.
Note: On Windows you may need to save your my.ini or my.cnf file with ANSI not UTF-8 encoding.
Use set global max_allowed_packet=104857600. This sets it to 100MB.
I had the same problem but changeing max_allowed_packet in the my.ini/my.cnf file under [mysqld] made the trick.
add a line
max_allowed_packet=500M
now restart the MySQL service once you are done.
I used following command in MySQL command-line to restore a MySQL database which size more than 7GB, and it works.
set global max_allowed_packet=268435456;
It may be easier to check if the connection exists and re-establish it if needed.
See PHP:mysqli_ping for info on that.
There are several causes for this error.
MySQL/MariaDB related:
wait_timeout - Time in seconds that the server waits for a connection to become active before closing it.
interactive_timeout - Time in seconds that the server waits for an interactive connection.
max_allowed_packet - Maximum size in bytes of a packet or a generated/intermediate string. Set as large as the largest BLOB, in multiples of 1024.
Example of my.cnf:
[mysqld]
# 8 hours
wait_timeout = 28800
# 8 hours
interactive_timeout = 28800
max_allowed_packet = 256M
Server related:
Your server has full memory - check info about RAM with free -h
Framework related:
Check settings of your framework. Django for example use CONN_MAX_AGE (see docs)
How to debug it:
Check values of MySQL/MariaDB variables.
with sql: SHOW VARIABLES LIKE '%time%';
command line: mysqladmin variables
Turn on verbosity for errors:
MariaDB: log_warnings = 4
MySQL: log_error_verbosity = 3
Check docs for more info about the error
Error: 2006 (CR_SERVER_GONE_ERROR)
Message: MySQL server has gone away
Generally you can retry connecting and then doing the query again to solve this problem - try like 3-4 times before completely giving up.
I'll assuming you are using PDO. If so then you would catch the PDO Exception, increment a counter and then try again if the counter is under a threshold.
If you have a query that is causing a timeout you can set this variable by executing:
SET ##GLOBAL.wait_timeout=300;
SET ##LOCAL.wait_timeout=300; -- OR current session only
Where 300 is the number of seconds you think the maximum time the query could take.
Further information on how to deal with Mysql connection issues.
EDIT: Two other settings you may want to also use is net_write_timeout and net_read_timeout.
In MAMP (non-pro version) I added
--max_allowed_packet=268435456
to ...\MAMP\bin\startMysql.sh
Credits and more details here
If you are using xampp server :
Go to xampp -> mysql -> bin -> my.ini
Change below parameter :
max_allowed_packet = 500M
innodb_log_file_size = 128M
This helped me a lot :)
This error is occur due to expire of wait_timeout .
Just go to mysql server check its wait_timeout :
mysql> SHOW VARIABLES LIKE 'wait_timeout'
mysql> set global wait_timeout = 600 # 10 minute or maximum wait time
out you need
http://sggoyal.blogspot.in/2015/01/2006-mysql-server-has-gone-away.html
I was getting this same error on my DigitalOcean Ubuntu server.
I tried changing the max_allowed_packet and the wait_timeout settings but neither of them fixed it.
It turns out that my server was out of RAM. I added a 1GB swap file and that fixed my problem.
Check your memory with free -h to see if that's what's causing it.
On windows those guys using xampp should use this path xampp/mysql/bin/my.ini and change max_allowed_packet(under section[mysqld])to your choice size.
e.g
max_allowed_packet=8M
Again on php.ini(xampp/php/php.ini) change upload_max_filesize the choice size.
e.g
upload_max_filesize=8M
Gave me a headache for sometime till i discovered this. Hope it helps.
It was RAM problem for me.
I was having the same problem even on a server with 12 CPU cores and 32 GB RAM. I researched more and tried to free up RAM. Here is the command I used on Ubuntu 14.04 to free up RAM:
sync && echo 3 | sudo tee /proc/sys/vm/drop_caches
And, it fixed everything. I have set it under cron to run every hour.
crontab -e
0 * * * * bash /root/ram.sh;
And, you can use this command to check how much free RAM available:
free -h
And, you will get something like this:
total used free shared buffers cached
Mem: 31G 12G 18G 59M 1.9G 973M
-/+ buffers/cache: 9.9G 21G
Swap: 8.0G 368M 7.6G
In my case it was low value of open_files_limit variable, which blocked the access of mysqld to data files.
I checked it with :
mysql> SHOW VARIABLES LIKE 'open%';
+------------------+-------+
| Variable_name | Value |
+------------------+-------+
| open_files_limit | 1185 |
+------------------+-------+
1 row in set (0.00 sec)
After I changed the variable to big value, our server was alive again :
[mysqld]
open_files_limit = 100000
This generally indicates MySQL server connectivity issues or timeouts.
Can generally be solved by changing wait_timeout and max_allowed_packet in my.cnf or similar.
I would suggest these values:
wait_timeout = 28800
max_allowed_packet = 8M
If you are using the 64Bit WAMPSERVER, please search for multiple occurrences of max_allowed_packet because WAMP uses the value set under [wampmysqld64] and not the value set under [mysqldump], which for me was the issue, I was updating the wrong one. Set this to something like max_allowed_packet = 64M.
Hopefully this helps other Wampserver-users out there.
There is an easier way if you are using XAMPP.
Open the XAMPP control panel, and click on the config button in mysql section.
Now click on the my.ini and it will open in the editor. Update the max_allowed_packet to your required size.
Then restart the mysql service. Click on stop on the Mysql service click start again. Wait for a few minutes.
Then try to run your Mysql query again. Hope it will work.
It's always a good idea to check the logs of the Mysql server, for the reason why it went away.
It will tell you.
MAMP 5.3, you will not find my.cnf and adding them does not work as that max_allowed_packet is stored in variables.
One solution can be:
Go to http://localhost/phpmyadmin
Go to SQL tab
Run SHOW VARIABLES and check the values, if it is small then run with big values
Run the following query, it set max_allowed_packet to 7gb:
set global max_allowed_packet=268435456;
For some, you may need to increase the following values as well:
set global wait_timeout = 600;
set innodb_log_file_size =268435456;
For Vagrant Box, make sure you allocate enough memory to the box
config.vm.provider "virtualbox" do |vb|
vb.memory = "4096"
end
This might be a problem of your .sql file size.
If you are using xampp. Go to the xampp control panel -> Click MySql config -> Open my.ini.
Increase the packet size.
max_allowed_packet = 2M -> 10M
The unlikely scenario is you have a firewall between the client and the server that forces TCP reset into the connection.
I had that issue, and I found our corporate F5 firewall was configured to terminate inactive sessions that are idle for more than 5 mins.
Once again, this is the unlikely scenario.
uncomment the ligne below in your my.ini/my.cnf, this will split your large file into smaller portion
# binary logging format - mixed recommended
# binlog_format=mixed
TO
# binary logging format - mixed recommended
binlog_format=mixed
I found the solution to "#2006 - MySQL server has gone away" this error.
Solution is just you have to check two files
config.inc.php
config.sample.inc.php
Path of these files in windows is
C:\wamp64\apps\phpmyadmin4.6.4
In these two files the value of this:
$cfg['Servers'][$i]['host']must be 'localhost' .
In my case it was:
$cfg['Servers'][$i]['host'] = '127.0.0.1';
change it to:
"$cfg['Servers'][$i]['host']" = 'localhost';
Make sure in both:
config.inc.php
config.sample.inc.php files it must be 'localhost'.
And last set:
$cfg['Servers'][$i]['AllowNoPassword'] = true;
Then restart Wampserver.
To change phpmyadmin user name and password
You can directly change the user name and password of phpmyadmin through config.inc.php file
These two lines
$cfg['Servers'][$i]['user'] = 'root';
$cfg['Servers'][$i]['password'] = '';
Here you can give new user name and password.
After changes save the file and restart WAMP server.
I got Error 2006 message in different MySQL clients software on my Ubuntu desktop. It turned out that my JDBC driver version was too old.
I had the same problem in docker adding below setting in docker-compose.yml:
db:
image: mysql:8.0
command: --wait_timeout=800 --max_allowed_packet=256M --character-set-server=utf8 --collation-server=utf8_general_ci --default-authentication-plugin=mysql_native_password
volumes:
- ./docker/mysql/data:/var/lib/mysql
- ./docker/mysql/dump:/docker-entrypoint-initdb.d
ports:
- 3306:3306
environment:
MYSQL_ROOT_PASSWORD: ${MYSQL_ROOT_PASSWORD}
MYSQL_DATABASE: ${MYSQL_DATABASE}
MYSQL_USER: ${MYSQL_USER}
MYSQL_PASSWORD: ${MYSQL_PASSWORD}
I also encountered this error. But even with the increased max_allowed_packet or any increase of value in the my.cnf, the error still persists.
What I did is I troubleshoot my database:
I checked the tables where the error persists
Then I checked each row
There are rows that are okay to fetch and there are rows where the error only shows up
It seems that there are value in these rows that is causing this error
But even by selecting only the primary column, the error still shows up (SELECT primary_id FROM table)
The solution that I thought of is to reimport the database. Good thing is I have a backup of this database. But I only dropped the problematic table, then import my backup of this table. That solved my problem.
My takeaway of this problem:
Always have a backup of your database. Either manually or thru CRON job
I noticed that there are special characters in the affected rows. So when I recovered the table, I immediately changed the collation of this table from latin1_swedish_ci to utf8_general_ci
My database was working fine before then my system suddenly encountered this problem. Maybe it also has something to do with the upgrade of the MySQL database by our hosting provider. So frequent backup is a must!
Just in case this helps anyone:
I got this error when I opened and closed connections in a function which would be called from several parts of the application.
We got too many connections so we thought it might be a good idea to reuse the existing connection or throw it away and make a new one like so:
public static function getConnection($database, $host, $user, $password){
if (!self::$instance) {
return self::newConnection($database, $host, $user, $password);
} elseif ($database . $host . $user != self::$connectionDetails) {
self::$instance->query('KILL CONNECTION_ID()');
self::$instance = null;
return self::newConnection($database, $host, $user, $password);
}
return self::$instance;
}
Well turns out we've been a little too thorough with the killing and so the processes doing important things on the old connection could never finish their business.
So we dropped these lines
self::$instance->query('KILL CONNECTION_ID()');
self::$instance = null;
and as the hardware and setup of the machine allows it we increased the number of allowed connections on the server by adding
max_connections = 500
to our configuration file. This fixed our problem for now and we learned something about killing mysql connections.
For users using XAMPP, there are 2 max_allowed_packet parameters in C:\xampp\mysql\bin\my.ini.
This error happens basically for two reasons.
You have a too low RAM.
The database connection is closed when you try to connect.
You can try this code below.
# Simplification to execute an SQL string of getting a data from the database
def get(self, sql_string, sql_vars=(), debug_sql=0):
try:
self.cursor.execute(sql_string, sql_vars)
return self.cursor.fetchall()
except (AttributeError, MySQLdb.OperationalError):
self.__init__()
self.cursor.execute(sql_string, sql_vars)
return self.cursor.fetchall()
It mitigates the error whatever the reason behind it, especially for the second reason.
If it's caused by low RAM, you either have to raise database connection efficiency from the code, from the database configuration, or simply raise the RAM.
For me it helped to fix one's innodb table's corrupted index tree. I localized such a table by this command
mysqlcheck -uroot --databases databaseName
result
mysqlcheck: Got error: 2013: Lost connection to MySQL server during query when executing 'CHECK TABLE ...
as followed I was able to see only from the mysqld logs /var/log/mysqld.log which table was causing troubles.
FIL_PAGE_PREV links 2021-08-25T14:05:22.182328Z 2 [ERROR] InnoDB: Corruption of an index tree: table `database`.`tableName` index `PRIMARY`, father ptr page no 1592, child page no 1234'
The mysqlcheck command did not fix it, but helped to unveil it.
Ultimately I fixed it as followed by a regular mysql command from a mysql cli
OPTIMIZE table theCorruptedTableNameMentionedAboveInTheMysqld.log