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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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
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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 ...
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 ...
31
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5answers
24k 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 ...
2
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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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5answers
3k views

Handling concurrent access to a key table without deadlocks in SQL Server

I have a table that is used by a legacy application as a substitute for IDENTITY fields in various other tables. Each row in the table stores the last used ID LastID for the field named in IDName. ...
9
votes
3answers
632 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 ...
7
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1answer
3k views

Deadlock error isn't returning the deadlock SQL

Transaction (Process ID) was deadlocked on lock resources with another process and has been chosen as the deadlock victim. Rerun the transaction. I am getting this error randomly when one of my ...
6
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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 ...
3
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2answers
797 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 ...
7
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2answers
2k 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 ...
5
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1answer
581 views

Deadlocks in SQL Server

We're currently encountering a problem with out ASP.NET Application that results in deadlocks on the SQL Server database. A bit of background information I can provide is that we rely heavy on AJAX ...
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2answers
548 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 ...
14
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1answer
1k views

Can foreign keys cause deadlocks and hinder READ COMITTED 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/timout situations in ...
4
votes
3answers
392 views

Does Snapshot Isolation only give you what has been commited? (And General Snapshot Isolation questions.)

So, I have some deadlocking issues. I have seen two options to resolve it. Add read uncommitted to my db or do Snapshot Isolation and add read committed snapshot. After doing some research into ...
4
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3answers
596 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 ...
2
votes
1answer
1k 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 ...
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2answers
2k 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
1answer
797 views

DB2 Communication link failure issue

I would like to get your valuable suggestions for the below problem. My Perl application connects to a DB2 database and keeps inserting data into a table. The application successfully inserts data ...
0
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3answers
2k views

How to avoid deadlock while updating 2 rows in MySQL

This is a interview problem: There is a perl program that updates the database, and it could run in different processes. One process may execute a transaction like: update row A -> update ...
0
votes
1answer
505 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
1answer
197 views

What would be possible reasons for a DeadLock to occur in Mysql Database?

If some one has a Table structure some thing like this, CREATE TABLE IF NOT EXISTS `domain_source` (`nid` int(11) NOT NULL DEFAULT '0', `domain_id` int(11) NOT NULL DEFAULT '0', PRIMARY KEY (`nid`) ) ...