Tagged Questions

1
vote
1answer
52 views

How can I make a select statement get blocked?

Hello I am trying to intentionally make a SQL select statement get blocked by another simple SQL delete or update statement, for the purpose of learning. I prefer only InnoDB tables. To prepare the ...
2
votes
1answer
52 views

When and why can this kind of deadlock occur?

------------------------ LATEST DETECTED DEADLOCK ------------------------ 130409 0:40:58 *** (1) TRANSACTION: TRANSACTION 3D61D41F, ACTIVE 3 sec inserting mysql tables in use 1, locked 1 LOCK WAIT ...
0
votes
1answer
140 views

How I prevent deadlock occurrence in my application?

I am developing an LMS application in PHP framework(Codeigniter 2.1.0). I am using MySQL database. All the tables in the database have innodb engine. I also created indexes on each tables. Now I am ...
0
votes
2answers
168 views

MySQL InnoDB locking on combined UPDATE-JOIN statements

on querying statements which contain an UPDATE combined with JOIN, we are getting the following errors: Statements writing to a table with an auto-increment column after selecting from another table ...
0
votes
0answers
90 views

innodb deadlock on different tables

I am using mysql 5.5.28. I would like to ask a question about the nature of deadlocks in innodb engine. I monitor deadlock with pt-deadlock-logger. Recently I found deadlock of two transactions to ...
0
votes
2answers
146 views

How long can Deadlock info hold in innodb status page?

When I run SHOW ENGINE INNODB STATUS\G, I can see this timestamp ------------------------ LATEST DETECTED DEADLOCK ------------------------ 121118 17:14:31 Questions Any idea how long Deadlock ...
1
vote
2answers
848 views

How to analyse innodb status on deadlock in insert Query?

I have a dead lock which i have posted here. I managed to get the innodb status from my server. Here is the Innodb status. OS WAIT ARRAY INFO: reservation count 247864, signal count 247470 Mutex ...
2
votes
3answers
2k views

How can I configure MySQL Innodb to handle 1000s of inserts per hour?

I have a very high traffic website where it is possible that 1000s of new records are inserted every hour. This one error is crippling the site: PDOException: SQLSTATE[40001]: Serialization failure: ...
2
votes
1answer
353 views

InnoDB : Deadlock from one reader and one writer

This sort of has me miffed. One query is doing a select that includes a table that is undergoing a heavy UPDATE, but that update takes under 1/2 a second, and there are no other writers to that ...
3
votes
2answers
421 views

Cannot update certain rows in innodb tables

I found the following on http://dev.mysql.com/doc/refman/5.1/en/innodb-deadlock-detection.html When InnoDB performs a complete rollback of a transaction, all locks set by the transaction are ...
6
votes
2answers
1k views

MySQL deadlock - cannot restart normally?

MySQL version 5.5.13-1 A snippet from the SHOW ENGINE INNODB STATUS\G: LATEST DETECTED DEADLOCK ------------------------ 111218 10:22:34 *** (1) TRANSACTION: TRANSACTION 1318D95B, ACTIVE 0 sec ...
3
votes
1answer
1k views

How do you read MySQL InnoDB Monitor output?

I am new to DB Administration. I am trying to figure out the cause of deadlock exceptions, but I am unable to make sense of the logs. The log says that "transaction 1 is rolled back". Why is this the ...
2
votes
2answers
693 views

Preventing mysql deadlocks in your php application that uses SELECT… LOCK IN SHARE MODE

If I understand SELECT ... LOCK IN SHARE MODE correctly, you can place it into a mysql transaction to select the rows you will be working with during that transaction. This is done in order to "lock ...
4
votes
3answers
513 views

Is Oracle DB immune to the InnoDB deadlocks found in MySQL?

It seems odd to me that MySQL would not handle this internally: "Deadlock found when trying to get lock; try restarting transaction" Does Oracle DB work around this issue? After all, Oracle owns ...
5
votes
1answer
2k views

Are InnoDB Deadlocks exclusive to INSERT/UPDATE/DELETE?

I am Working around MySQL error "Deadlock found when trying to get lock; try restarting transaction". I am going to have to update a program to allow deadlocks. Is it possible that SELECT statement ...
4
votes
2answers
2k views

Will these two queries result in a deadlock if executed in sequence?

This is almost certainly the cause of my other question, but I thought it was worth separating the two as I have a hypothesis based on the following log that I would love to have falsified or ...
6
votes
2answers
2k views

Trouble deciphering a deadlock in an innodb status log

We are accessing MySQL from the Microsoft ADO.NET connector. Occasionally we are seeing the following deadlock in our innodb status and haven't been able to identify the cause of the problem. It ...