MySQL General Log Not Starting on 'Set Global' - mysql

I am trying to set up my MySQL general log so that it can be switched on and off by using
SET GLOBAL general_log = 'ON'
SET GLOBAL general_log = 'OFF'
I would like it off by default (i.e. on server startup) but then have the ability to toggle it as above, so that I don't have to keep restarting the server. When I attempt to switch general logging ON as above, MySQL generates the following error:
Table 'mysql.general_log' doesn't exist
This is true - I have purposely not created this table as I would like logging to occur to file - NOT to tables. This suggests to me that that MySQL is trying to log the general queries to table even though the relevant global variables are set as below:
log_output = FILE
general_log = OFF
general_log_file = /var/log/mysql-general.log
The relevant part of the my.cnf is as follows:
[mysqld]
general-log = OFF
general-log-file = /var/log/mysql-general.log
I am using MySQL version 5.1.58 on a Linux server.
Thanks in advance,
Andy

Since the table mysql.general_log does not exist, I assume you upgraded from a previous version of MySQL and need to run mysql_upgrade to create them.
Backup all of your databases using mysqldump and do a filesystem backup of /var/lib/mysql, then execute the following commands:
mysql_upgrade -p --force
followed by
service mysql restart
or
/etc/init.d/mysql restart
If the general_log table still does not exist after taking these steps, follow the steps in this post: MySql - I dropped general_log table to manually create it.

Related

LOAD_FILE returns only null

I want to insert the image to the database with this query:
SELECT LOAD_FILE('/Users/juliagaskevich/cool-background.svg');
I checked that:
File size < max_allowed_packet.
File has read, write and execute permissions to everyone.
The user, what I'm using to execute the query has FILE privilege.
mysql> show variables like "secure_file_priv" returns NULL.
System configuration:
macOS Monterey, version 12.5, chip Apple M1
MySQL Ver 8.0.29 for macos12 on arm64 (MySQL Community Server - GPL)
MySQL Config:
[mysqld]
user = mysql_deamon
slow_query_log_file = my-slow-query.log
slow-query-log
log-queries-not-using-indexes
general_log_file = my-GENERAL.log
max_allowed_packet = 1073741824
Also, I tried to fix my problem with guys' ideas, but...
1.vi my.cnf
secure-file-priv=/mysql/dataload(Change /mysql/dataload to your own
directory.)
2.restart mysql service
Changed my.cnf
Changed my.cnf (without quotes in secure-file-priv path)
The statement SELECT LOAD_FILE(...) delivers one string. To INSERT,
use the statement LOAD DATA INFILE ...
1290 ERROR with null secure_file_priv result
1.vi my.cnf
secure-file-priv=/mysql/dataload(Change /mysql/dataload to your own directory.)
2.restart mysql service
The statement SELECT LOAD_FILE(...) delivers one string. To INSERT, use the statement LOAD DATA INFILE ...
SOLVING
If you are using mac, you have the /etc/my.cnf (file, where is MySQL config stored), so put there this string secure_file_priv = ""
Run this to apply config changes mysqld --defaults-file=/etc/my.cnf --validate-config --log_error_verbosity=2 AND IF you have any warnings or errors fix it, because it can solve your problem
If you are using some different user than root, the user have to have a FILE privileges mysql> GRANT privilege ON privilege_level TO account_name;, for example mysql> GRANT FILE ON *.* TO pizzaadmin;
The most important thing: To apply changes, you have to restart mysqld.
There are few steps:
stop it (You can do this with this command mysqladmin shutdown)
start again (You can do this with just executing mysqld in terminal)

ERROR 2006 (HY000): MySQL server has gone away

I get this error when I try to source a large SQL file (a big INSERT query).
mysql> source file.sql
ERROR 2006 (HY000): MySQL server has gone away
No connection. Trying to reconnect...
Connection id: 2
Current database: *** NONE ***
ERROR 2006 (HY000): MySQL server has gone away
No connection. Trying to reconnect...
Connection id: 3
Current database: *** NONE ***
Nothing in the table is updated. I've tried deleting and undeleting the table/database, as well as restarting MySQL. None of these things resolve the problem.
Here is my max-packet size:
+--------------------+---------+
| Variable_name | Value |
+--------------------+---------+
| max_allowed_packet | 1048576 |
+--------------------+---------+
Here is the file size:
$ ls -s file.sql
79512 file.sql
When I try the other method...
$ ./mysql -u root -p my_db < file.sql
Enter password:
ERROR 2006 (HY000) at line 1: MySQL server has gone away
max_allowed_packet=64M
Adding this line into my.cnf file solves my problem.
This is useful when the columns have large values, which cause the issues, you can find the explanation here.
On Windows this file is located at: "C:\ProgramData\MySQL\MySQL Server
5.6"
On Linux (Ubuntu): /etc/mysql
You can increase Max Allowed Packet
SET GLOBAL max_allowed_packet=1073741824;
http://dev.mysql.com/doc/refman/5.5/en/server-system-variables.html#sysvar_max_allowed_packet
The global update and the my.cnf settings didn't work for me for some reason. Passing the max_allowed_packet value directly to the client worked here:
mysql -h <hostname> -u username -p --max_allowed_packet=1073741824 <databasename> < db.sql
In general the error:
Error: 2006 (CR_SERVER_GONE_ERROR) - MySQL server has gone away
means that the client couldn't send a question to the server.
mysql import
In your specific case while importing the database file via mysql, this most likely mean that some of the queries in the SQL file are too large to import and they couldn't be executed on the server, therefore client fails on the first occurred error.
So you've the following possibilities:
Add force option (-f) for mysql to proceed and execute rest of the queries.
This is useful if the database has some large queries related to cache which aren't relevant anyway.
Increase max_allowed_packet and wait_timeout in your server config (e.g. ~/.my.cnf).
Dump the database using --skip-extended-insert option to break down the large queries. Then import it again.
Try applying --max-allowed-packet option for mysql.
Common reasons
In general this error could mean several things, such as:
a query to the server is incorrect or too large,
Solution: Increase max_allowed_packet variable.
Make sure the variable is under [mysqld] section, not [mysql].
Don't afraid to use large numbers for testing (like 1G).
Don't forget to restart the MySQL/MariaDB server.
Double check the value was set properly by:
mysql -sve "SELECT ##max_allowed_packet" # or:
mysql -sve "SHOW VARIABLES LIKE 'max_allowed_packet'"
You got a timeout from the TCP/IP connection on the client side.
Solution: Increase wait_timeout variable.
You tried to run a query after the connection to the server has been closed.
Solution: A logic error in the application should be corrected.
Host name lookups failed (e.g. DNS server issue), or server has been started with --skip-networking option.
Another possibility is that your firewall blocks the MySQL port (e.g. 3306 by default).
The running thread has been killed, so retry again.
You have encountered a bug where the server died while executing the query.
A client running on a different host does not have the necessary privileges to connect.
And many more, so learn more at: B.5.2.9 MySQL server has gone away.
Debugging
Here are few expert-level debug ideas:
Check the logs, e.g.
sudo tail -f $(mysql -Nse "SELECT ##GLOBAL.log_error")
Test your connection via mysql, telnet or ping functions (e.g. mysql_ping in PHP).
Use tcpdump to sniff the MySQL communication (won't work for socket connection), e.g.:
sudo tcpdump -i lo0 -s 1500 -nl -w- port mysql | strings
On Linux, use strace. On BSD/Mac use dtrace/dtruss, e.g.
sudo dtruss -a -fn mysqld 2>&1
See: Getting started with DTracing MySQL
Learn more how to debug MySQL server or client at: 26.5 Debugging and Porting MySQL.
For reference, check the source code in sql-common/client.c file responsible for throwing the CR_SERVER_GONE_ERROR error for the client command.
MYSQL_TRACE(SEND_COMMAND, mysql, (command, header_length, arg_length, header, arg));
if (net_write_command(net,(uchar) command, header, header_length,
arg, arg_length))
{
set_mysql_error(mysql, CR_SERVER_GONE_ERROR, unknown_sqlstate);
goto end;
}
I solved the error ERROR 2006 (HY000) at line 97: MySQL server has gone away and successfully migrated a >5GB sql file by performing these two steps in order:
Created /etc/my.cnf as others have recommended, with the following contents:
[mysql]
connect_timeout = 43200
max_allowed_packet = 2048M
net_buffer_length = 512M
debug-info = TRUE
Appending the flags --force --wait --reconnect to the command (i.e. mysql -u root -p -h localhost my_db < file.sql --verbose --force --wait --reconnect).
Important Note: It was necessary to perform both steps, because if I didn't bother making the changes to /etc/my.cnf file as well as appending those flags, some of the tables were missing after the import.
System used: OSX El Capitan 10.11.5; mysql Ver 14.14 Distrib 5.5.51 for osx10.8 (i386)
Just in case, to check variables you can use
$> mysqladmin variables -u user -p
This will display the current variables, in this case max_allowed_packet, and as someone said in another answer you can set it temporarily with
mysql> SET GLOBAL max_allowed_packet=1072731894
In my case the cnf file was not taken into account and I don't know why, so the SET GLOBAL code really helped.
You can also log into the database as root (or SUPER privilege) and do
set global max_allowed_packet=64*1024*1024;
doesn't require a MySQL restart as well. Note that you should fix your my.cnf file as outlined in other solutions:
[mysqld]
max_allowed_packet=64M
And confirm the change after you've restarted MySQL:
show variables like 'max_allowed_packet';
You can use the command-line as well, but that may require updating the start/stop scripts which may not survive system updates and patches.
As requested, I'm adding my own answer here. Glad to see it works!
The solution is increasing the values given the wait_timeout and the connect_timeout parameters in your options file, under the [mysqld] tag.
I had to recover a 400MB mysql backup and this worked for me (the values I've used below are a bit exaggerated, but you get the point):
[mysqld]
port=3306
explicit_defaults_for_timestamp = TRUE
connect_timeout = 1000000
net_write_timeout = 1000000
wait_timeout = 1000000
max_allowed_packet = 1024M
interactive_timeout = 1000000
net_buffer_length = 200M
net_read_timeout = 1000000
set GLOBAL delayed_insert_timeout=100000
Blockquote
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.
A couple things could be happening here;
Your INSERT is running long, and client is disconnecting. When it reconnects it's not selecting a database, hence the error. One option here is to run your batch file from the command line, and select the database in the arguments, like so;
$ mysql db_name < source.sql
Another is to run your command via php or some other language. After each long - running statement, you can close and re-open the connection, ensuring that you're connected at the start of each query.
If you are on Mac and installed mysql through brew like me, the following worked.
cp $(brew --prefix mysql)/support-files/my-default.cnf /usr/local/etc/my.cnf
Source: For homebrew mysql installs, where's my.cnf?
add max_allowed_packet=1073741824 to /usr/local/etc/my.cnf
mysql.server restart
I had the same problem in XAMMP
Metode-01: I changed max_allowed_packet in the D:\xampp\mysql\bin\my.ini file like that below:
max_allowed_packet=500M
Finally restart the MySQL service once and done.
Metode-02:
the 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.
I encountered this error when I use Mysql Cluster, I do not know this question is from a cluster usage or not. As the error is exactly the same, so give my solution here.
Getting this error because the data nodes suddenly crash. But when the nodes crash, you can still get the correct result using cmd:
ndb_mgm -e 'ALL REPORT MEMORYUSAGE'
And the mysqld also works correctly.So at first, I can not understand what is wrong. And about 5 mins later, ndb_mgm result shows no data node working. Then I realize the problem. So, try to restart all the data nodes, then the mysql server is back and everything is OK.
But one thing is weird to me, after I lost mysql server for some queries, when I use cmd like show tables, I can still get the return info like 33 rows in set (5.57 sec), but no table info is displayed.
This error message also occurs when you created the SCHEMA with a different COLLATION than the one which is used in the dump. So, if the dump contains
CREATE TABLE `mytab` (
..
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
you should also reflect this in the SCHEMA collation:
CREATE SCHEMA myschema COLLATE utf8_unicode_ci;
I had been using utf8mb4_general_ci in the schema, cause my script came from a fresh V8 installation, now loading a DB on old 5.7 crashed and drove me nearly crazy.
So, maybe this helps you saving some frustating hours... :-)
(MacOS 10.3, mysql 5.7)
Add max_allowed_packet=64M to [mysqld]
[mysqld]
max_allowed_packet=64M
Restart the MySQL server.
If it's reconnecting and getting connection ID 2, the server has almost definitely just crashed.
Contact the server admin and get them to diagnose the problem. No non-malicious SQL should crash the server, and the output of mysqldump certainly should not.
It is probably the case that the server admin has made some big operational error such as assigning buffer sizes of greater than the architecture's address-space limits, or more than virtual memory capacity. The MySQL error-log will probably have some relevant information; they will be monitoring this if they are competent anyway.
This is more of a rare issue but I have seen this if someone has copied the entire /var/lib/mysql directory as a way of migrating their DB to another server. The reason it doesn't work is because the database was running and using log files. It doesn't work sometimes if there are logs in /var/log/mysql. The solution is to copy the /var/log/mysql files as well.
For amazon RDS (it's my case), you can change the max_allowed_packet parameter value to any numeric value in bytes that makes sense for the biggest data in any insert you may have (e.g.: if you have some 50mb blob values in your insert, set the max_allowed_packet to 64M = 67108864), in a new or existing parameter-group. Then apply that parameter-group to your MySQL instance (may require rebooting the instance).
For Drupal 8 users looking for solution for DB import failure:
At end of sql dump file there can commands inserting data to "webprofiler" table.
That's I guess some debug log file and is not really important for site to work so all this can be removed. I deleted all those inserts including LOCK TABLES and UNLOCK TABLES (and everything between). It's at very bottom of the sql file. Issue is described here:
https://www.drupal.org/project/devel/issues/2723437
But there is no solution for it beside truncating that table.
BTW I tried all solutions from answers above and nothing else helped.
I've tried all of above solutions, all failed.
I ended up with using -h 127.0.0.1 instead of using default var/run/mysqld/mysqld.sock.
If you have tried all these solutions, esp. increasing max_allowed_packet up to the maximum supported amount of 1GB and you are still seeing these errors, it might be that your server literally does not have enough free RAM memory available...
The solution = upgrade your server to more RAM memory, and try again.
Note: I'm surprised this simple solution has not been mentioned after 8+ years of discussion on this thread... sometimes we developers tend to overthink things.
Eliminating the errors which triggered Warnings was the final solution for me. I also changed the max_allowed_packet which helped with smaller files with errors. Eliminating the errors also sped up the process incredibly.
if none of this answers solves you the problem, I solved it by removing the tables and creating them again automatically in this way:
when creating the backup, first backup structure and be sure of add:
DROP TABLE / VIEW / PROCEDURE / FUNCTION / EVENT
CREATE PROCEDURE / FUNCTION / EVENT
IF NOT EXISTS
AUTO_INCREMENT
then just use this backup with your db and it will remove and recreate the tables you need.
Then you backup just data, and do the same, and it will work.
How about using the mysql client like this:
mysql -h <hostname> -u username -p <databasename> < file.sql

Setting global sql_mode in MySQL

I am trying to set sql_mode in MySQL but it throws an error.
Command:
set global sql_mode='NO_BACKSLASH_ESCAPES','STRICT_TRANS_TABLE','NO_AUTO_CREATE_USER','NO_ENGINE_SUBSTITUTION'
Is this not the proper way to set multiple modes?
What are the advantages of setting session and global modes?
Which is preferred?
I have different users trying to update the database with different UNC values and instead of setting the session mode to NO_BACKSLASH_ESCAPES, I though it would make sense to set a global mode for this. Does this make sense?
Please let me know.
Thanks.
BTW, if you set globals in MySQL:
SET GLOBAL sql_mode = 'NO_ENGINE_SUBSTITUTION';
SET SESSION sql_mode = 'NO_ENGINE_SUBSTITUTION';
This will not set it PERMANENTLY, and it will revert after every restart.
So you should set this in your config file (e.g. /etc/mysql/my.cnf in the [mysqld] section), so that the changes remain in effect after MySQL restart:
Config File: /etc/mysql/my.cnf
[mysqld]
sql_mode = NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
UPDATE: Newer versions of Mysql (e.g. 5.7.8 or above) may require slightly different syntax:
[mysqld]
sql-mode="STRICT_TRANS_TABLES,NO_ENGINE_SUBSTITUTION"
Make sure that there is a dash between sql-mode not an underscore, and that modes are in double quotes.
Always reference the MySQL Docs for your version to see the sql-mode options.
I resolved it.
the correct mode is :
set global sql_mode="NO_BACKSLASH_ESCAPES,STRICT_TRANS_TABLE,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
Setting sql mode permanently using mysql config file.
In my case i have to change file /etc/mysql/mysql.conf.d/mysqld.cnf as mysql.conf.d is included in /etc/mysql/my.cnf. i change this under [mysqld]
[mysqld]
sql_mode = "STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
just removed ONLY_FULL_GROUP_BY sql mode cause it was causing issue.
I am using ubuntu 16.04, php 7 and mysql --version give me this mysql Ver 14.14 Distrib 5.7.13, for Linux (x86_64) using EditLine wrapper
After this change run below commands
sudo service mysql stop
sudo service mysql start
Now check sql modes by this query SELECT ##sql_mode and you should get modes that you have just set.
For someone who googling this error for MySQL 8.
MySQL 8.0.11 remove the 'NO_AUTO_CREATE_USER' from sql-mode.
MySQL 5.7: Using GRANT to create users. Instead, use CREATE USER.
Following this practice makes the NO_AUTO_CREATE_USER SQL mode
immaterial for GRANT statements, so it too is deprecated. MySQL
8.0.11: Using GRANT to create users. Instead, use CREATE USER. Following this practice makes the NO_AUTO_CREATE_USER SQL mode
immaterial for GRANT statements, so it too is removed.
Taken from here
So, your sql_mode can be like this:
sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION
Or if you're using Docker you can add next command to docker-compose.yml
mysql:
image: mysql:8.0.13
command: --sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION
ports:
- 13306:${MYSQL_PORT}
Copy to Config File: /etc/mysql/my.cnf OR /bin/mysql/my.ini
[mysqld]
port = 3306
sql-mode=""
MySQL restart.
Or you can also do
[mysqld]
port = 3306
SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
MySQL restart.
Access the database as the administrator user (root maybe).
Check current SQL_mode
mysql> SELECT ##sql_mode;
To set a new sql_mode, exit the database, create a file
nano /etc/mysql/conf.d/<filename>.cnf
with your sql_mode content
[mysqld]
sql_mode=NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
Restart Mysql
mysql> sudo service mysql stop
mysql> sudo service mysql start
We create a file in the folder /etc/mysql/conf.d/
because in the main config file /etc/mysql/my.cnf
the command is written to include all the settings files from the folder /etc/mysql/conf.d/
For Temporary change use following command
set global sql_mode="NO_BACKSLASH_ESCAPES,STRICT_TRANS_TABLE,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
For permanent change : go to config file /etc/my.cnf or /etc/mysql/mysql.conf.d/mysqld.cnf and add following lines then restart mysql service
[mysqld]
sql_mode = "STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
Check the documentation of sql_mode
Method 1:
Check default value of sql_mode:
SELECT ##sql_mode //check current value for sql_mode
SET GLOBAL sql_mode = "NO_BACKSLASH_ESCAPES,STRICT_TRANS_TABLE,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION";
Method 2:
Access phpmyadmin for editing your sql_mode
Login on phpmyadmin and open localhost
Top on Variables present on the top in menu items and search out for sql mode
Click on edit button to modify sql_mode based on your requirements
Save the changes
Restart server after executing above things
In my case mysql and ubuntu 18.04
I set it permanently using this command
sudo nano /etc/mysql/mysql.conf.d/mysqld.cnf
Append the line after the configuration. See example highlighted in the image below.
sql_mode = ""
Note :You can also add different modes here, it depends on your need
NO_BACKSLASH_ESCAPES,STRICT_TRANS_TABLE,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
See Available sql modes reference and Documentation
Then save.
After saving you need to restart your mysql service, follow the command below:
sudo service mysql restart
Hope this helps :-)
In my case i have to change file /etc/mysql/mysql.conf.d/mysqld.cnf change this under [mysqld]
Paste this line on [mysqld] portion
sql_mode = "STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
I just had a similar problem where MySQL (5.6.45) wouldn't accept sql_mode from any config file.
The solution was to add init_file = /etc/mysql/mysql-init.sql to the config file and then execute SET GLOBAL sql_mode = ''; in there.
If someone want to set it only for the current session then use the following command
set session sql_mode="NO_BACKSLASH_ESCAPES,STRICT_TRANS_TABLE,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
Updating this for users Using MAMP PRO {works with MAMP users too}. Because I seem to have got stuck on finding a solution for this, but people recommended I should edit the my.cnf file in the /Applications/MAMP/tmp/mysql/my.cnf folder which does not work because it gets reset after every restart of mysql server.
Referring this document:
The configuration file “my.cnf” of MySQL can be found here:
“/Applications/MAMP/tmp/mysql/my.cnf”. Please note: Editing this file
does NOT work as it will be overwritten every time MySQL is restarted
by MAMP PRO with a “my.cnf” file that is created from the MySQL
template. You must edit this template (menu File > Open Template >
MySQL (my.cnf) > 5.7.30) to modify the MySQL configuration. Manually
adding “my.cnf” files to other locations is not recommended. Every
configuration aspect can be handled with the MySQL template.
Once this is done, add the following in the my.cnf file:
[mysqld]
sql_mode = STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
Restart the Mysql Server. That should do the trick.
set global sql_mode="NO_BACKSLASH_ESCAPES,STRICT_TRANS_TABLE,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"

How to show the last queries executed on MySQL?

Is there any query/way to show the last queries executed on ALL servers?
For those blessed with MySQL >= 5.1.12, you can control this option globally at runtime:
Execute SET GLOBAL log_output = 'TABLE';
Execute SET GLOBAL general_log = 'ON';
Take a look at the table mysql.general_log
If you prefer to output to a file instead of a table:
SET GLOBAL log_output = "FILE"; the default.
SET GLOBAL general_log_file = "/path/to/your/logfile.log";
SET GLOBAL general_log = 'ON';
I prefer this method to editing .cnf files because:
you're not editing the my.cnf file and potentially permanently turning on logging
you're not fishing around the filesystem looking for the query log - or even worse, distracted by the need for the perfect destination. /var/log /var/data/log /opt /home/mysql_savior/var
You don't have to restart the server and interrupt any current connections to it.
restarting the server leaves you where you started (log is by default still off)
For more information, see
MySQL 5.1 Reference Manual - Server System Variables - general_log
You can enable a general query log for that sort of diagnostic. Generally you don't log all SELECT queries on a production server though, it's a performance killer.
Edit your MySQL config, e.g. /etc/mysql/my.cnf - look for, or add, a line like this
[mysqld]
log = /var/log/mysql/mysql.log
Restart mysql to pick up that change, now you can
tail -f /var/log/mysql/mysql.log
Hey presto, you can watch the queries as they come in.
SELECT * FROM mysql.general_log WHERE command_type ='Query' LIMIT total;
You can do the flowing thing for monitoring mysql query logs.
Open mysql configuration file my.cnf
sudo nano /etc/mysql/my.cnf
Search following lines under a [mysqld] heading and uncomment these lines to enable log
general_log_file = /var/log/mysql/mysql.log
general_log = 1
Restart your mysql server for reflect changes
sudo service mysql start
Monitor mysql server log with following command in terminal
tail -f /var/log/mysql/mysql.log
1) If general mysql logging is enabled then we can check the queries in the log file or table based what we have mentioned in the config.
Check what is enabled with the following command
mysql> show variables like 'general_log%';
mysql> show variables like 'log_output%';
If we need query history in table then
Execute SET GLOBAL log_output = 'TABLE';
Execute SET GLOBAL general_log = 'ON';
Take a look at the table mysql.general_log
If you prefer to output to a file:
SET GLOBAL log_output = "FILE"; which is set by default.
SET GLOBAL general_log_file = "/path/to/your/logfile.log";
SET GLOBAL general_log = 'ON';
2) We can also check the queries in the .mysql_history file
cat ~/.mysql_history
Maybe you could find that out by looking at the query log.
If you don't feel like changing your MySQL configuration you could use an SQL profiler like "Neor Profile SQL" http://www.profilesql.com .
If mysql binlog is enabled you can check the commands ran by user by executing
following command in linux console by browsing to mysql binlog directory
mysqlbinlog binlog.000001 > /tmp/statements.sql
enabling
[mysqld]
log = /var/log/mysql/mysql.log
or general log will have an effect on performance of mysql
After reading Paul's answer, I went on digging for more information on https://dev.mysql.com/doc/refman/5.7/en/query-log.html
I found a really useful code by a person. Here's the summary of the context.
(Note: The following code is not mine)
This script is an example to keep the table clean which will help you to reduce your table size. As after a day, there will be about 180k queries of log. ( in a file, it would be 30MB per day)
You need to add an additional column (event_unix) and then you can use this script to keep the log clean... it will update the timestamp into a Unix-timestamp, delete the logs older than 1 day and then update the event_time into Timestamp from event_unix... sounds a bit confusing, but it's working great.
Commands for the new column:
SET GLOBAL general_log = 'OFF';
RENAME TABLE general_log TO general_log_temp;
ALTER TABLE `general_log_temp`
ADD COLUMN `event_unix` int(10) NOT NULL AFTER `event_time`;
RENAME TABLE general_log_temp TO general_log;
SET GLOBAL general_log = 'ON';
Cleanup script:
SET GLOBAL general_log = 'OFF';
RENAME TABLE general_log TO general_log_temp;
UPDATE general_log_temp SET event_unix = UNIX_TIMESTAMP(event_time);
DELETE FROM `general_log_temp` WHERE `event_unix` < UNIX_TIMESTAMP(NOW()) - 86400;
UPDATE general_log_temp SET event_time = FROM_UNIXTIME(event_unix);
RENAME TABLE general_log_temp TO general_log;
SET GLOBAL general_log = 'ON';
Credit goes to Sebastian Kaiser (Original writer of the code).
Hope someone will find it useful as I did.
You can look at the following in linux
cd /root
ls -al
vi .mysql_history It may help

MySQL Error 1153 - Got a packet bigger than 'max_allowed_packet' bytes

I'm importing a MySQL dump and getting the following error.
$ mysql foo < foo.sql
ERROR 1153 (08S01) at line 96: Got a packet bigger than 'max_allowed_packet' bytes
Apparently there are attachments in the database, which makes for very large inserts.
This is on my local machine, a Mac with MySQL 5 installed from the MySQL package.
Where do I change max_allowed_packet to be able to import the dump?
Is there anything else I should set?
Just running mysql --max_allowed_packet=32M … resulted in the same error.
You probably have to change it for both the client (you are running to do the import) AND the daemon mysqld that is running and accepting the import.
For the client, you can specify it on the command line:
mysql --max_allowed_packet=100M -u root -p database < dump.sql
Also, change the my.cnf or my.ini file (usually found in /etc/mysql/) under the mysqld section and set:
max_allowed_packet=100M
or you could run these commands in a MySQL console connected to that same server:
set global net_buffer_length=1000000;
set global max_allowed_packet=1000000000;
(Use a very large value for the packet size.)
As michaelpryor said, you have to change it for both the client and the daemon mysqld server.
His solution for the client command-line is good, but the ini files don't always do the trick, depending on configuration.
So, open a terminal, type mysql to get a mysql prompt, and issue these commands:
set global net_buffer_length=1000000;
set global max_allowed_packet=1000000000;
Keep the mysql prompt open, and run your command-line SQL execution on a second terminal..
This can be changed in your my.ini file (on Windows, located in \Program Files\MySQL\MySQL Server) under the server section, for example:
[mysqld]
max_allowed_packet = 10M
Re my.cnf on Mac OS X when using MySQL from the mysql.com dmg package distribution
By default, my.cnf is nowhere to be found.
You need to copy one of /usr/local/mysql/support-files/my*.cnf to /etc/my.cnf and restart mysqld. (Which you can do in the MySQL preference pane if you installed it.)
The fix is to increase the MySQL daemon’s max_allowed_packet. You can do this to a running daemon by logging in as Super and running the following commands.
# mysql -u admin -p
mysql> set global net_buffer_length=1000000;
Query OK, 0 rows affected (0.00 sec)
mysql> set global max_allowed_packet=1000000000;
Query OK, 0 rows affected (0.00 sec)
Then to import your dump:
gunzip < dump.sql.gz | mysql -u admin -p database
In etc/my.cnf try changing the max_allowed _packet and net_buffer_length to
max_allowed_packet=100000000
net_buffer_length=1000000
if this is not working then try changing to
max_allowed_packet=100M
net_buffer_length=100K
On CENTOS 6 /etc/my.cnf , under [mysqld] section the correct syntax is:
[mysqld]
# added to avoid err "Got a packet bigger than 'max_allowed_packet' bytes"
#
net_buffer_length=1000000
max_allowed_packet=1000000000
#
I have resolved my issue by this query
SET GLOBAL max_allowed_packet=1073741824;
and check max_allowed_packet with this query
SHOW VARIABLES LIKE 'max_allowed_packet';
Use a max_allowed_packet variable issuing a command like
mysql --max_allowed_packet=32M
-u root -p database < dump.sql
Slightly unrelated to your problem, so here's one for Google.
If you didn't mysqldump the SQL, it might be that your SQL is broken.
I just got this error by accidentally having an unclosed string literal in my code. Sloppy fingers happen.
That's a fantastic error message to get for a runaway string, thanks for that MySQL!
Error:
ERROR 1153 (08S01) at line 6772: Got a packet bigger than
'max_allowed_packet' bytes Operation failed with exitcode 1
QUERY:
SET GLOBAL max_allowed_packet=1073741824;
SHOW VARIABLES LIKE 'max_allowed_packet';
Max value:
Default Value (MySQL >= 8.0.3) 67108864
Default Value (MySQL <= 8.0.2) 4194304
Minimum Value 1024
Maximum Value 1073741824
Sometimes type setting:
max_allowed_packet = 16M
in my.ini is not working.
Try to determine the my.ini as follows:
set-variable = max_allowed_packet = 32M
or
set-variable = max_allowed_packet = 1000000000
Then restart the server:
/etc/init.d/mysql restart
It is a security risk to have max_allowed_packet at higher value, as an attacker can push bigger sized packets and crash the system.
So, Optimum Value of max_allowed_packet to be tuned and tested.
It is to better to change when required (using set global max_allowed_packet = xxx)
than to have it as part of my.ini or my.conf.
I am working in a shared hosting environment and I have hosted a website based on Drupal. I cannot edit the my.ini file or my.conf file too.
So, I deleted all the tables which were related to Cache and hence I could resolve this issue. Still I am looking for a perfect solution / way to handle this problem.
Edit - Deleting the tables created problems for me, coz Drupal was expecting that these tables should be existing. So I emptied the contents of these tables which solved the problem.
Set max_allowed_packet to the same (or more) than what it was when you dumped it with mysqldump. If you can't do that, make the dump again with a smaller value.
That is, assuming you dumped it with mysqldump. If you used some other tool, you're on your own.