I've a page which selects data from a table based on the primary key of the table
ex: SELECT * FROM table_name WHERE id=primary_key_value
As soon as I execute this from my CI page, I'm getting following error message
"Mysql server has gone away"
I searched in mysql reference manual, they are telling, its the cause of "wait_timeout" in configuration file. My configuration file has following settings
wait_timeout = 10
Could someone help me resolve this issue?
MySQL Server Has Gone Away - MySQL 5.5
link
Another one
Related
I want to make an average of forex_askprice and forex_bidprice and insert into forex_midprice. like this
update eurusd_tickdata_2017 set forex_midprice=(forex_askprice+forex_bidprice)/2
But I met this error
2003 - Can't connect to MySQL server on 'localhost' (10061 "Unknown error")
时间: 759.205s'
There are around 40,000,000 rows in the table eurusd_tickdata_2017
it was the problem on your configuration settings of your database source like connection look up this video for your issue.
https://www.youtube.com/watch?v=ab25N34RO8w
It looks like your MySQL server is not installed. you can check steps & install from link - MySQL on Windows
In the joomla 3.7 site, everything was running OK. But last night suddenly it has gone totally down, throwing error msg
"Application Instantiation Error: Could not connect to MySQL"
The last operation performed by me was editing a comment as admin. When clicked "SAVE" after editing, the error appeared. The tables were MYIASM.
The check_database or repair_database option in cpanel also do not respond. In phpMyAdmin, I can view the table list but running any query is halting with error
"Lost connection to MySQL server during query
.
Can not back up the database either from cpanel or phomyadmin or mysqldump.
2006 - MySQL server has gone away
But I have another drupal database in the same host. Tt is serving the site and all the above operation work on it without any problem.
The joomla db was in myIASM format. after all errors, I tried to convert the tables to InnoDB. But the ALTER TABLE query also halted in middle. Some tables are Innodb and some are MYIASM now.
Please help me to solve the problem.
Update:
After some checking, I found that the database is throwing error as
already has more than 'max_user_connections' active connections when
trying to connect
But there is no active connection visible in "show processlist"
In your .cfg or .ini,
log_warnings=2 for logging to your error log, including connection failure details.
To determine how many connections are possible,
SHOW GLOBAL VARIABLES LIKE 'max_connections'
and increase by 10% with
max_connections=(newlimit)
both within [mysqld], shutdown, restart
remember SET GLOBAL general_log=1 will track everything MySQL is trying to do for your analysis when you are having troubles.
Remember to turn OFF general_log before you go to lunch (or anywhere).
I know this question has been asked on here before, but it seems like I've tried everything suggested in this answer and this answer, and still no luck. I'm trying to use MySQL Workbench 6.3 on a Windows 10 client, connecting to a Linux MySQL server hosted by GoDaddy/cPanel.
I can connect to the MySQL server with no problems, and usually I have time to run a query or two. Then, within a minute of inactivity between Workbench and the server, I'll run into Error 2013: Lost connection to MySQL server during query. This even happens when running the exact same query, back to back about a minute apart, as shown here (even when the original query is quick; only 0.03 seconds to run):
The same problem persists when I run select sleep(60) immediately upon connecting to the MySQL Server; the connection is usually lost between 30-40 seconds into the execution of the query:
I've checked the MySQL docs, but with no luck. I don't think the problem can be related to packet size, as others have suggested (since the same query will work and then fail later), and my Workbench timeout settings look okay:
Anyone have any idea? The only other thing I can think of is maybe the wait_timeout variable listed in the MySQL docs needs to be increased too, but I guess that would be somewhere on the server side (some have mention my.ini) and I can't find where any MySQL Server files live in the cPanel hosting admin interface. There's a MySQL online client provided through cPanel (phpMyAdmin I think), but it's not nearly as robust and is becoming cumbersome to use. Any help would be appreciated!
I was having the same problem, using MySQL Workbench 6.3.6 on Win10 to connect to a MySQL server on a shared hosting system (Arvixe).
In addition to to the problem described by the OP (lost connection to server), I was also getting an error when attempting to import data from a prior export (similar to what is described here):
Unhandled exception: Error querying security information: Error executing 'SELECT * FROM mysql.user WHERE user = '[username]' and Host = '[host]' ORDER BY User, Host' SELECT command denied to user '[username]'#'[host]' for table 'user' SQL Error: 1142
Apparently, a bug was introduced in MySQL Workbench 6.3.5 (bug report). From the bug report:
It appears the problem arise if connecting with an user with no privileges on the mysql schema.
In other words: users connecting to a shared hosting system.
The proposed solution is to uninstall MySQL Workbench 6.3.6, and install 6.3.4 instead. (6.3.4 can be found in the archives). This solution worked for me.
Today my datacenter had a breaker fail which resulted in my servers losing power. I'm running a 4 node MySQL cluster. I restarted the cluster, first the management nodes, then the data nodes, then after the data nodes were running I started the SQL nodes. I then checked the cluster with ndb_mgm -e SHOW. Everything seemed fine until I tried running a query. I got this error,
ERROR 1296 (HY000): Got error 157 'Unknown error code' from NDBCLUSTER
I check the MySQL logs and could not find any errors. I then tried a full shutdown and restart of the MySQL cluster and checked config between the shutdown and start. Everything seemed to check out. I then ran a query on another database using the NDBCLUSTER engine. The query was successful. I've tried searching google but no one seems to have any answers that help. I've checked the config, I've made sure ndbd is running on the data nodes, ect. The other databases seem to be working fine except this one. I have a backup of the database but I would much preferably recover the database if possible.
If anyone has any suggestion or ideas, it would be greatly appreciated.
Thanks in advance.
Error 157 is actually 'could not connect to storage engine' and the fact that MySQL fails to report that error correctly is a bug: http://bugs.mysql.com/bug.php?id=44817
The case described in that bug mentions that you get the error when you try to query a table in NDB when the cluster is still down.
So I'm just guessing, but I would conclude that your cluster is not started. Either you missed starting one of the nodes, or else something went wrong starting one of the nodes.
Check the mysql server is really connected to the NDB storage.
Do from a mysql server that should be connected to NDB
SHOW GLOBAL STATUS LIKE 'Ndb_cluster_node_id';
Is the answer > 0?
SHOW GLOBAL STATUS LIKE 'Ndb_number_of_data_nodes';
Is the answer > 0 ?
If not, then the mysql server is not connected and then i would recommend you check your firewall and /etc/hosts table and make sure you dont have a line like:
127.0.0.1 localhost ..
Best regards
Johan
My web threw the error "MySQL server has gone away". I google it, find a method that use mysql_ping function, but I use extension mysqli, not mysql.
How can I fix this problem?
There is a mysqli_ping method for this, as well:
http://us3.php.net/manual/en/mysqli.ping.php
However, in my experience, ping was not needed. All I had to do was add mysqli.reconnect = "1" to my php.ini.
Ref. check if mysql connection is valid
You may get this error when your query is crashing MySQL server check MySQL error log file for that.
If values for wait_timeout & interactive_timeout MySQL server variables is set to very low in MySQL configuration file. Try increasing values for them and then restart MySQL server.
This is basically a time between two queries and after opening new connection if you don't execute next query before this timeout then your connection will be automatically closed by the MySQL server and you will get this error.
Stop and start mysql server to fix this problem.