A situation caused by two or more processes being unable to proceed (and thus release their locks) because they are blocked by locks on resources held by the other process.

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9
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3answers
646 views

Need Help Troubleshooting Sql Server 2005 Deadlock Scenario

I am running into a deadlock scenario where the only participants in the deadlock appear to be a single table and a single stored procedure that deletes from that table. I drew that conclusion based ...
4
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1answer
3k 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
1k 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 ...
15
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1answer
2k views

Can foreign keys cause deadlocks and hinder READ COMMITTED SNAPSHOT?

This is a followup question from: http://stackoverflow.com/questions/7684477/is-it-possible-to-set-transaction-isolation-level-snapshot-automatically I'm still having deadlock/timeout situations in ...
5
votes
2answers
7k views

can I resolve a deadlock with the rowlock hint?

I have a large delete stored proc and I've reproduced a deadlock in a situation where the deletes would not have deleted anything. It looks like the part of the stored proc that hit a deadlock was ...
10
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3answers
14k views

Notification on long-running query or deadlock in SQL Server 2008 R2?

I'd like to know if there is a way to send a notification on deadlock? If so what queries would be required. I understand that SQL Server takes care of deadlocks, I simply would like information on ...
2
votes
1answer
419 views

Locking, deadlocking workaround while process data at the same table

My database has a table: tableX. Task1 makes intensive INSERTs (1000 records per minute) as records to process and very seldom UPDATEs (1-2 records per minute) as records to recalculate. At the ...
4
votes
3answers
630 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
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1answer
3k 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 ...
5
votes
2answers
3k 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
3k 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 ...
7
votes
4answers
9k views

How to monitor deadlocks

When do you start troubleshooting a SQL Server 2005/2008 deadlocks and how? The alert is turned on SSMS via SQL Server performance condition alert, objects->SQLServer:Locks, Counter->Lock Waits/Sec, ...
7
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1answer
3k views

SQL Server Deadlock Graph - Table, Page or Row Lock?

Is there any way to decipher if a lock in a deadlock graph is Table, Page or Row level? I have all the information I need from the graph, including the Isolation Level, (2) but I really want to know ...
7
votes
2answers
4k views

Why does this query cause a deadlock?

Why does this query cause a deadlock? UPDATE TOP(1) system_Queue SET [StatusID] = 2, @ID = InternalID WHERE InternalID IN ( SELECT TOP 1 InternalID FROM system_Queue WHERE ...
4
votes
2answers
3k views

Determine Reason for Deadlock in MySQL

We've been seeing some deadlocks occur but have not been able to reproduce. Is there any way to determine, after the fact, what queries were running, etc to figure out why deadlock occurred?
6
votes
3answers
580 views

Inserting and updating and selecting at thousands of times per second

I have a table that gets inserted, updated and selected from thousands of times within one second. I am having deadlock issues though. The database has 2-5 simultaneous 1000+ row inserts using Linq ...
15
votes
3answers
8k views

Code to simulate deadlock

I am testing my application I need some code that stable simulates the deadlock on database site (sql script if possible). Thank you. ADDED: Reproducing deadlocks involving only one table
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votes
6answers
27k views

What are the main causes of deadlocks and can they be prevented?

Recently one of our ASP.NET applications displayed a database deadlock error and I was requested to check and fix the error. I managed to find the cause of the deadlock was a stored procedure that ...