MySQL server global error log - mysql

I need to capture all of the query errors that are happening on my MySQL server. I've looked into the general_log and that appears to just save the queries, but NOT the result (whether there was an error thrown or not). I've heard some people say the server can't do this, and it can only be done on the client. This seems like a common function, so I would be surprised if there was no option to log query errors on the server.
How can I log these query errors?

There is no error.log in MySQL like you desire, see here what you can log with MySQL.
The only way is to look in your own error.logs e.g. in php:
catch the mysql_error or mysqli_error in php and write your own log-file
or
look in your apache-error-log when you didn´t catch your errors

Related

View MySQL *query* errors/warnings in AWS RDS

How do I view MySQL query errors and warnings in RDS? I am still using MySQL 5.6.
I have looked in the log files (under Log & Events), but they remain empty even when I do a query that generates an error in the console. For example, I ran a query that gave me error 1054 (unknown column), but nothing appeared in the error log. I've realized that this isn't the type of errors that get logged.
The log_warnings parameter is set to 1. I've tried setting general_log=1, but that generates way to much info, and still doesn't log the errors.
The reason that I need this is that I am upgrading from 5.6 to 5.7. I need like to see what warnings I'm currently getting since some warning will become errors in 5.7, and need to be fixed.
You can run SHOW WARNINGS immediately after the query, to get all conditions (errors, warnings, and notes). You have to do this in the client that ran the query. It's not a log.
There is no log for error, warnings, or notes for each query. The errors and warnings in the MySQL Server error log are for server errors, not for individual queries.
Queries that can't be parsed are not written to the general log or the slow query log by default. If you set the global option log_raw=1 then the general log will log erroneous queries, but still won't log the error itself. Even with that option, the slow query log won't log queries that can't be parsed.
A free tool from Percona may be helpful for your testing. pt-upgrade allows you to use a query log file as input, and it runs the query against two instances of MySQL, and reports any difference in errors or warnings, or results.
I thought of another partial solution: the PERFORMANCE_SCHEMA has tables for statement events. The statement event tables have columns for error number and message caused by each query, if any. But only a count of the warnings, not the warning message(s) themselves.

MySQL Query running even after losing connection

I've a MySQL 5.1.41 Server installed on a Ubuntu machine. I get connected to it through Workbench from my Windows machine over TCP/IP. I run a bigger query, after 900 seconds I got the below message, (there is no wait_timeout defined in the server's configuration file my.cnf)
Error Code: 2013. Lost connection to MySQL server during query
But when I look into the process list by using show processlist; command, I can still see my query running.
I got this link http://dev.mysql.com/doc/refman/5.0/en/gone-away.html where I found the below lines,
The problem on Windows is that in some cases MySQL does not get an
error from the OS when writing to the TCP/IP connection to the server,
but instead gets the error when trying to read the answer from the
connection.
I'm not sure whether this is the reason for my observation.
Please clarify me on this.
Thanks in advance!!
Closing connection is not a reason to stop a query. A query might be update, or kind of transaction, or select with output to remote (server) file.
Closed connection is just is just means, that you will not receive any data from DBMS after executing query (data, timings - nothing).
The reason of closing connection could be different, as SO-User posted. Try increasing
on server side:
wait_timeout
max_allowed_packet
on client side:
any kinds of timeout you find in your client (i.e. that SO-User suggests)
Do not forget to reload DBMS config and restart client (for sure)
In MySQL WorkBench we have an option to change timeout.
Find it under
Edit → Preferences → SQL Editor → DBMS connection read time out (in seconds): 600
Changed the value to 6000 or something higher.
Update
Lost connection to MySQL server
There are three likely causes for this error message.
Usually it indicates network connectivity trouble and you should check
the condition of your network if this error occurs frequently. If the
error message includes “during query,” this is probably the case you
are experiencing.
Sometimes the “during query” form happens when millions of rows are
being sent as part of one or more queries. If you know that this is
happening, you should try increasing net_read_timeout from its default
of 30 seconds to 60 seconds or longer, sufficient for the data
transfer to complete.
More rarely, it can happen when the client is attempting the initial
connection to the server. In this case, if your connect_timeout value
is set to only a few seconds, you may be able to resolve the problem
by increasing it to ten seconds, perhaps more if you have a very long
distance or slow connection. You can determine whether you are
experiencing this more uncommon cause by using SHOW GLOBAL STATUS LIKE
'Aborted_connects'. It will increase by one for each initial
connection attempt that the server aborts. You may see “reading
authorization packet” as part of the error message; if so, that also
suggests that this is the solution that you need.
If the cause is none of those just described, you may be experiencing
a problem with BLOB values that are larger than max_allowed_packet,
which can cause this error with some clients. Sometime you may see an
ER_NET_PACKET_TOO_LARGE error, and that confirms that you need to
increase max_allowed_packet.
Doc link: Error lost connection
and also check here

MySQL log failed query attempts

It is a purely MySQL tweaking question on logging the failed SQL attempts.
I need a solution to log the failed SQLs on the MySQL database.
The MySQL general query log does not work here, because it will log only the successful queries only. I need to know the failed ones in a different log file.
My scenario is: I need to cleanup a big messy SQLs and PHP Scripts (literally, around 7,000 SQLs being executed per page). Since the errors are suppressed on the server, even the SQLs failed queries will continue and show the good contents on the website. But I am sure, there are a lot of SQL errors. I found 2 links but cannot retry. This one and writing server side audit plugin in MySQL.
Is using Kontrolbase an answer as mentioned here.
Percona Server 5.5.37 and 5.6.17 include an implementation of an audit plugin which is free and open-source. Read about it here: http://www.percona.com/doc/percona-server/5.6/management/audit_log_plugin.html
The audit plugin logs both successful queries and erroneous queries. Here's an example where I queried my table foo and then a non-existent table foobar:
<AUDIT_RECORD
"NAME"="Query"
"RECORD"="489_2014-05-23T14:06:09"
"TIMESTAMP"="2014-05-23T14:08:13 UTC"
"COMMAND_CLASS"="select"
"CONNECTION_ID"="32709"
"STATUS"="0"
"SQLTEXT"="select * from foo"
"USER"="root[root] # localhost []"
"HOST"="localhost"
"OS_USER"=""
"IP"=""
/>
<AUDIT_RECORD
"NAME"="Query"
"RECORD"="490_2014-05-23T14:06:09"
"TIMESTAMP"="2014-05-23T14:08:19 UTC"
"COMMAND_CLASS"="select"
"CONNECTION_ID"="32709"
"STATUS"="1146"
"SQLTEXT"="select * from foobar"
"USER"="root[root] # localhost []"
"HOST"="localhost"
"OS_USER"=""
"IP"=""
/>
STATUS=1146 is indicated for the error query above. See http://dev.mysql.com/doc/refman/5.6/en/error-messages-server.html to reference server errors. For example, 1146 is ER_NO_SUCH_TABLE.
If you can't use this solution, then you'll have to change your PHP code to remove the error suppression, and log the errors.

Difference In Phpmyadmin Mysql web client and Terminal client

I got problem (#2006 Mysql server gone away) with mysql while connecting and performing some operations through web browser.
Operation Listed below:
When Executing big procedure
Importing database dump
When Access some particular tables It immediately throws "Server gone away".
Refer this question for Scenarios: Record Not Inserted - #2006 Mysql server gone away
Note : The above operations are works fine when I perform through terminal.
I tried some configuration as googing stated. That is set wait_timeout, max_allowed_packet. I checked for the bin_log but it is not available.
But the issues will not rectified.
What is the problem & How can I figure out & fix the issue?
what is the different between access phpmyadmin mysql server from web browser and terminal?
Where I can find the mysql server log file?
Note: If you know about any one of the above questions. Please post here. It would be helpful to trace.
Please help me to figure this out..
Thanks in advance...
Basically nothing except phpMyAdmin is limited by PHP's timeout and resource limits (limits to keep a runaway script from bogging down your entire machine for all eternity; see the docs for details of those values. In some cases, you might be authenticating through a different user account (for instance, root#localhost and root#127.0.0.1 aren't the same user), but as long as you're using a user with the same permissions the differences are minimal.
You can read more about logs in the MySQL manual, note that "By default, no logs are enabled (except the error log on Windows)".
Below are answer for question
From my research the problem is that browser have some limit to disconnect the connection i.e timeout connection. So that the above problem raised.
To resolve this problem
Go to /opt/lampp/phpmyadmin and open config.inc.php
add the command $cfg['ExecTimeLimit'] = 0;
Restart the xamp server. Now you can perform any operations.
`
2. Web client is differ from terminal because Terminal client will not getting timeout. Terminal client maintain the connection till the progress completed. I recommenced to use command prompt to import/export/run process by safe way.
Basically phpmyadmin will not have any log file. If you wanna see warnings and error you should configure the log file.
Configuration steps:
Go to /opt/lampp/etc/my.cnf
Add log_bin = /opt/lampp/var/mysql/filename.log
Restart the xamp server. You can get the log information.

"MySQL server has gone away" in mysqli

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.