I'm using MySQL workbench to run a query. The query is reasonably big. When I limit the results to say 50 records the results are as expected. But when I remove the limit, the query runs for ~ 5 minutes then prompts me to re-enter my password. After doing so I see the query has not run and has stopped working.
It seems like there is a setting that kicks me off after a certain amount of time but I cannot see it in the drop down menus.
Has anyone experienced this? Any advice?
** Update**
Query ran and Workbench says results returned but they are not and I got the screen shot error pop up here:
It sounds like one of three things are the likely culprit.
MySql Workbench may be timing out.
This may help with #1
Go to Edit -> Preferences -> SQL Editor and set to a higher value this
parameter: DBMS connection read time out (in seconds). For instance:
86400.
Close and reopen MySQL Workbench. Kill your previously query that
probably is running and run the query again.
The mySQL server is timing out
You will need access to the server's timeout configuration
Something network related (but far less likely if your timeout happens consistently at around 5 mins)
There are a number of factors that might need adjusting.
If #2, you will need access to the server's timeout configuration
If #3, well, there are a number of factors that might need adjusting.
Related
I have a MySQL database that I am running very simple queries against as part of a webapp. I have received reports from users starting today that they got an error saying that their account doesn't exist, and when they log in again, it does (this happened to only a few people, and only once to each, so clearly it is rare). Based on my backend code, this error can only occur if the same query returns 0 row the first time, and 1 row the second. My query is basically SELECT * FROM users WHERE username="...". How is this possible? My suspicion is that the hard disk is having I/O failures, but I am unsure because I would not expect MySQL to fail silently in this case. That said, I don't know what else it could be.
This could be a bug with your mysql client (Though I'm unsure as to how the structure of your code is, it could just be bad query). However let's assume that your query has been working fine up until now with no prior issues, so we'll rule out bad code.
With that in mind, I'm assuming it's either a bug in your mysql client or your max connection count is reached (Had this issue with my previous host - Hostinger).
Let's say your issue is a bug in your mysql client, set your sessions to per session basis by running this
SET SESSION optimizer_switch="index_merge_intersection=off";
or in your my.cnf you can set it globally
[mysqld] optimizer_switch=index_merge_intersection=off
As for max connection you can either increase your max_connection value (depending if your host allows it), or you'll have to make a logic to close the mysql connection after a query execution.
$mysqli->close();
I am working on converting unix time to readable time.
It is necessary to insert a 6gb .txt file into my database
(XAMPP V3.2.2 , MYSQL workbench 5.2.34).
I have written the SQL query to convert unix time but whenever i run the query, Mysql workbench will crash
(error:2013.lost connection to database during query.).why?
my SQL query:UPDATE database.database SET readable_time=from_unixtime(unix_time);
Increasing net_read_timeout solves this problem
From doc:
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.
Click here for more info.
Please check this post - Error Code: 2013. Lost connection to MySQL server during query
As you are talking about an insert, understand that the 'Workbench' loses the connection, but the query continues to execute in the 'server'. That is, the workbench can no longer update you on the status changes for that query execution. But, the execution of the query keeps continuing behind screens.
You might want to run show processlist to see if the insert process is still running or not.
However, while fetching data from the database, you might have to update your timeout settings.
I have a very strange problem on my server. My site is on a dedicated host, and runs very well. But sometimes when I'm running a very simple query like:
UPDATE product SET active = 1 WHERE id_product = 99
I feel that sometimes, I would even say the first time that day (?!) MySQL literally crashed. Even the MySQL service becomes impossible to restart, and I have to reboot my server. If I re-execute the same query, then it takes 0.001 second.
This problem can arrive on any UPDATE query. I try to repair all these tables, I even delete the database + re-create the problem remains the same.
I do not know what can be the problem? Someone has an idea? :(
I am getting the error stated in my post title. I have two tables. The first one, large is over than 4000,000 records and the second, small one is arounf 7000 records. I want to search for the value in the samll table and if found, I want to extract the whole record from the large table. The command never executed and always lose the connection with the database. I tried to limit the out put to 50 records only, the same thing happens. Please help me. If I need something like indexing (I read this might solve such performance problems, please clarify to me how. I'm not a DBA).
select * from db.large, db.small
where large.value=small.value;
*EDIT: * I use MySQL workbench 5.2.41 CE.
At one point on a previous project, I could actually crash the MySQL server reproducibly with a pretty simple query. In the code that called the database, I saw the same error message. Can you verify that the MySQL server's process ID is the same before and after the query? Chances are that your OS restarts the MySQL server immediately after the crash, and the MySQL command line client automatically reconnects (though it emits a notice when it does).
I have some strange bug into a application(or is it the MySQL build?) that causes queries to remain in "locked" state forever, filling up the max number of threads.
I read about setting the wait_timeout variable to kill the "bogus" threads after a period of time. This works ok, but I would like to log the killed queries for further inspection/making sure backup scripts are not killed.
Is there any possibility to do that?
Thanks.
You might be able to use the slow log, but I'm not sure if the problem is that they never complete. Worth a shot.
Also, you may be able to see what's going on by running SHOW FULL PROCESSLIST while you've got dead threads. It should show you what the problem is and what the query was.
If you can simulate this in a development environment, you could also turn on general query logging (which records every statement) and then just tail the log after it crashes.
In the past, I have tagged queries with a unique comment (per query type):
/* Query_12345 */ SELECT ... FROM ... WHERE ... LIMIT ...
A background process would poll SHOW FULL PROCESSLIST and look for any queries that were more than X seconds long, and tagged with Query_NNNNN.
Finally, it would kill them if they went on too long. This allowed the server to breath while we figured out how to optimize the 80,000,000 record table that was slowing things down.