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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View last several innodb deadlocks

I see that I can view the latest deadlock in mysql/innodb, but is there a way to view past deadlocks? We have two deadlock issues, one being important and the other not. The less important deadlock ...
3
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1answer
2k views

MySQL: Alter Table on very active table gives “Waiting for table metadata lock”

At my work, we've recently upgraded to MySQL 5.5 and since then, have been bitten a few times by the new (and intended) behavior of metadata locking. Basically, whenever we run an ALTER TABLE ...
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1answer
3k views

PAGELOCK Conversion Deadlock From Update to Intent Exclusive

A customer of ours is experiencing frequent deadlocks. The deadlocks are mostly on the same UPDATE statement. The deadlocks follow a pattern in which both SPIDs have acquired an update (U) lock on a ...
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1answer
2k 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 ...
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1answer
812 views

How this simple Stored Procedure ended up in Deadlock

Thanks for all and this forum is really helpful. After few minutes of system running we get “Try restarting the transaction.” And its end up in deadlock. We use MySQL 5.5.28 and the Java code ...
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2answers
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Shared and IX locks causing deadlock (Sql server)

In my environment, I have 2 tables - Issue and IssuePropertyValues (which has foreign key reference to the Issue table). Now, we insert values into these 2 tables using the below 2 queries: INSERT ...
3
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1answer
95 views

Merge causing deadlocks

We are running MS SQL Server 2008 R2. We've got a VendorMaster table (with about 8700 rows) that we are trying to keep in sync across two databases using a Merge statement. The merge code runs every ...
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1answer
182 views

Can a Table Lock eliminate a deadlock or make it worse Oracle

We have a situation in which an Oracle Database is having deadlocks issues. I said that perhaps we should lock into some table locks, and a guys response to me was "Unless I am misunderstanding ...
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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 ...
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2answers
9k views

How to find out what caused the database(DB2) in a locking state

I know how to check the DB is in a lock state or not, but my question is how to find out which query caused the lock on table /db. IS there any log file getting created if something unexpected ...
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56 views

MySQL queries waiting for other queries to finish

We have 30-40 different projects in Python and PHP that update, insert and select more than 1 million rows of data in MySQL DB every day. Currently we use InnoDB Engine for our tables. The problem: ...
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108 views

Read/Write Deadlock on Ms-Sql Server

We are facing deadlocks when store procedure is concurrently executed. We are using Microsoft SQL Server 2008 R2, concurrent execution is done with java executing multiple request of sp. I have ...
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176 views

How to set ALL the replication to DEADLOCK_PRIORITY LOW?

I have just got this email here: Then looking at the sql server log I find this deadlock was caused by one of our procedures (that was the victim) against the replication. O.K. in this case in ...
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Update+Select in one SQL Server transaction, and concurrent deadlocks [duplicate]

I have a problem with a transaction isolation or concurrent atomic select+update. SQL Server, C++ application, OTL/ODBC, and I can't use any stored procedures. Here is the thing. The task is to ...
3
votes
1answer
640 views

Intent Exclusive (IX) Lock questions [closed]

I was experiencing a deadlock so I set up a trace flags as well as profile trace to capture a deadlock. During this exercise I found something interesting. In the profile trace I noticed that "sa" ...
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2answers
2k views

Is problem with parallelism more common today than before? And what issues can arise from paralellism?

This is a very general question so I don't give much specific information. I am more interested in parallelism and its possible drawbacks. Generally I am all for parallelism as something useful and ...
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2answers
16k views

SQL Server - How many type of timeout can happen, and how?

When working with SQL Server, there can be multiple application host accessing it, and each application can have one or many connection. Each connection can potentially have multiple transaction (...
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1answer
2k views

How do you avoid a foreign key constraint creating deadlocks?

So I have two tables that create a deadlock. The application literally do nothing but update two different tables in two different transactions. There is a foreign key constraint (not cascading, just ...
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2answers
5k 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 ...
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2answers
6k views

Deadlock on Insert/Update

Using SQL Server 2008 R2: I'm currently attempting to track down the cause of a deadlock issue we have. Not sure where to turn. Here's the setup. TABLE Scores: id INT IDENTITY(1,1), first_name ...
2
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1answer
4k views

Cannot fetch the rowset from OLE DB provider “SQLNCLI” for linked server X

I am getting this error while doing concurrent read from same table through linked server. Time out setting is alright. When this error happens, I also start getting the following error for the same ...
2
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1answer
65 views

Update with CTE & OUTPUT blocks on concurrent calls

I was having deadlock issues, so I started using this CTE trick that I read somewhere. No more deadlocks. But now each client that I add slows down (blocks?) the sproc. E.g. a 1-2 second update with ...
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1answer
70 views

Hold exclusive lock on a whole DB

As I explained in Set a filegroup to readonly, I wanna set some tables readonly, to have better performance. These tables are only written by an ETL that runs daily, then they are only read. ...
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1answer
93 views

what are the costs of enabling extended events?

I have been dealing with deadlocks, specifically getting their information, as you can see on this post here. On this same post Shanky recommended "You must now rely on extended events trace to ...
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1answer
59 views

Trace flag is running, but not message when deadlock happens

Trace flags are used to temporarily set specific server characteristics or to switch off a particular behavior More information on the trace flags are here DBCC TRACESTATUS this above, is the ...
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1answer
1k 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 ...
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1answer
1k views

sp_getapplock doubt

We are using sp_getapplock as a transaction level in a procedure which in turn calls another procedure where again we use sp_getapplock with the same resource names. I wanted to know whether this ...
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2answers
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SQL Server deadlock too long [closed]

I have a really weird problem with a deadlock between a business process and a monitoring job. The both were involved on a deadlock that lasted around 5.5 hours. I don't know why SQL Server took so ...
2
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1answer
424 views

What happens if two mySQL queries both try to lock the same row at the same time?

So this isn't exactly my strong suit, but here's my basic understanding of the situation: If two threads of the same application both try to execute the same query at the same time, mySQL will ...
2
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1answer
625 views

How many rows will be locked by SELECT … ORDER BY xxx LIMIT 1 FOR UPDATE?

As was asked on stackoverflow but then for MySQL, I was wondering how this works in PostgreSQL. How many rows get locked when I do a "FOR UPDATE" in combination with a "LIMIT", a "ORDER BY" and some "...
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2answers
658 views

Help reading deadlock XML

Even with reading the Bart Duncan blog about reading deadlocks I still struggle with this. I have included the XML from a particular deadlock. <?xml version="1.0" encoding="utf-8" ?> - <...
2
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1answer
453 views

Why my application is blocked infinitely and SQL Server never timeout and kill the deadlock

I have a multi-thread application that can opened more than one database connection to perform database operation. These connections are using the same credential. Here is a problem, the application ...
2
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2answers
577 views

Alternatives to sp_indexoption for Row Locks and Page Locks in SQL Server 2008

Are there better alternatives to setting the Row Locks and Page Locks in SQL Server 2008? The case here is to set the row and page locks to false on the table. The lock is in effect during a series ...
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1answer
148 views

Extended Events XML querie to show relevant info about deadlocks - SQL Server 2014

While trying to get together information about deadlocks I came across this link which asks a question regarding a trace: Interpretation of a column in SQL Server profile trace The answer dealt with ...
2
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1answer
248 views

How do I understand this DeadLock Graph?

I'm attempting to decipher the content of this deadlock graph. Is there some way to view this information in a more visually meaningful way? Manually reading through the XML is hurting my eyes. <...
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2answers
190 views

Understanding deadlock XML

Recently a clients website has been receiving many deadlocks. The website and CMS is custom built on asp.net MVC 3. The database is SQL Server 2008. I believe this started occurring when there was ...
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2answers
1k views

Amazon rds MySql -> concurrent connections deadlocks

I normally hang around in StackOverflow but I think this issue is better suited here. I've built an application in C#.NET that uses MySql as a database. My application inserts and updates data in the ...
2
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1answer
372 views

How to use proper hints for Upsert involving a top 1 subquery

For this specific case (tracking Load Balancer switches) we wish to optimize an Upsert so that it does not exhibit any race conditions, cause any PK violation, or acquire any over sized locks. ...
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2answers
2k views

How to rollback the identity seed after deadlock

Now that's an approximate sequence of operations Im performing: SET IDENTITY_INSERT <table-name> ON; INSERT SOMETHING to <table-name> with explicitly specifyed id DECLARE @oldID bigint ...
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3answers
1k 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 ...
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1answer
13k views

Getting deadlock information easily

I know to check for live deadlocks select * from sys.sysprocesses where blocked>0 However, that is only for deadlocks that are current. How do we check for deadlocks from the say the last 24 hours? ...
2
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1answer
75 views

Why does Deadlock occur for this INSERT/UPDATE combination despite seemingly holding an X lock?

I am regularly seeing deadlocks in a production MySQL 5.5 database but cannot determine exactly what the cause is. For context, we're inserting new records into a database which are triggered by ...
2
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2answers
114 views

Where to look for possible deadlock causes?

We've been having several problems the past days in our production environment, and some of them seem to boil down to database issues. Just realized we are having deadlocks (68 actually), on database ...
2
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1answer
47 views

How to use two actions and a function in an Extended Events Histogram for deadlocks?

I'd like to get a histogram through extended events that shows the count of deadlocks per databasename by date, but I'm hitting two walls: How get a histogram to include two actions How to get the ...
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1answer
269 views

Two updates cause a deadlock

I have a mysql queue with the following sheme: CREATE TABLE IF NOT EXISTS `media` ( `mid` int(11) NOT NULL AUTO_INCREMENT, `order_type` int(11) NOT NULL, `media_id` varchar(50) COLLATE ...
2
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1answer
733 views

Why do these concurrent MySQL inserts deadlock?

I am baffled by this deadlock: ------------------------ LATEST DETECTED DEADLOCK ------------------------ 150511 18:42:43 *** (1) TRANSACTION: TRANSACTION B8972CA4, ACTIVE 0 sec inserting mysql ...
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1answer
93 views

How is it possible that two deletes give a deadlock, if they do have different primary key data

I am getting a deadlock by the same delete stored procedures that is called by two different threads for deleting two concurrent records. The deadlock happened on the primary key index of the X table....
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1answer
331 views

Deadlock occurring on database, SQL Server 2008R2

Last few days I had major problems with my production site, turns out deadlock occurred, every half an hour maybe 50-60 of them. To do a quick fix in order to keep the site running I set : ...
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2answers
619 views

Reducing deadlocks with update query hint or other method

I'm getting 20-30 deadlocks per day on the same table. (2 mil rows) Profiler DeadlockGraphs show KEY LOCK and PAGE LOCK (See attched jpg) Total datatype size per row = 114 bytes We have multiple ...
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1answer
7k 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 ...