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.

learn more… | top users | synonyms

2
votes
1answer
372 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
votes
2answers
500 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 ...
2
votes
2answers
633 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
votes
1answer
284 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. ...
2
votes
2answers
1k 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 ...
2
votes
1answer
1k 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
715 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 ...
2
votes
1answer
586 views

How do I understand this deadlock?

I have two threads doing inserts into a table at the same time, causing a deadlock. The interaction with the table is in a new transaction, so I'm pretty confident there is nothing else going on here. ...
2
votes
1answer
77 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 ...
2
votes
2answers
351 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 ...
2
votes
1answer
4k 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 ...
2
votes
1answer
813 views

mysql replication deadlock slave stopped

I've a master and slave and got the slave stopped with the following error log in slave. I want to fix this and get the two servers on synch and get going again. 111128 8:42:24 [Note] Slave I/O ...
2
votes
1answer
452 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 ...
2
votes
0answers
45 views

innodb update with limit locks all matching (ignores limit)

For a query similar to this: UPDATE myinnotable1 SET value=5,updated=now(),status=1 WHERE status>10 AND message="match msg" LIMIT 1; I found that innodb engine locks ALL rows matching criteria ...
2
votes
0answers
24 views

Locks while stream reading and deleting/inserting involving the same tables?

I have a question regarding a potential block/lock situation: I am reading data using a select command, which is then modified externally and uploaded to a temporary table. A stored procedure will ...
2
votes
1answer
259 views

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 ...
2
votes
0answers
276 views

Why does a simple select query produce a deadlock? [closed]

I am trying to analyze randomly occurring deadlock problems on an SQL Server 2008 R2 database. The deadlocks occur in very rare cases when SSRS tries to access one of 5 different stored procedures. ...
2
votes
0answers
92 views

Deadlock when CODES table has 41900 rows

I'm having a deadlock accessing the same table from two different jobs. I'm testing it on a SQL SERVER 2012 Enterprise edition. Running SQL Profiler I get this graph: You can find the SQL Server ...
2
votes
0answers
260 views

Read-Commited Snaphsot isolation causing deadlocks?

Our DBA has some type of process setup to monitor deadlocks and sends out an emails when a deadlocks occurs. We have been testing read committed snapshot isolation on our application for a couple ...
2
votes
0answers
4k views

Oracle Select Query Over Database Link Suddenly Hangs Endlessly

I have a query that's been in use for years and today it started hanging endlessly. I took the query apart and found the piece causing it to hang is a simple join on a primary key that should run like ...
2
votes
0answers
395 views

SQL Server 2008 R2 - Deadlock Trace, Need Help Understanding It

I really need help on understanding this deadlock, i've already replaced the values, mind if anyone helps me interpreting where my deadlocks are coming from? What does e_waitpipegetrow mean? btw, i'm ...
2
votes
1answer
541 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" ...
2
votes
1answer
209 views

SSMS Object Explorer Details causes deadlock while job is running

I have a problem with one of my SQL Server jobs. I've found that while the job is running, SQL Server Management Studio locks up. It always locks up while I'm looking at tables and sprocs within the ...
1
vote
2answers
1k 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 ...
1
vote
1answer
2k views

Understanding Deadlock graph on one table

I do not understand this deadlock graph that we are experiencing on this table (I have had to redact the exact column names) I have not had much exposure to deadlocks outside of reading material and ...
1
vote
1answer
56 views

How does the table scan in an UPDATE WHERE predicated on an unindexed column work?

I was looking into a deadlock caused by two concurrent UPDATE statements: UPDATE [table] SET [column] = 0 WHERE [unindexed_column] = @id My understanding is that because the column the WHERE is ...
1
vote
2answers
4k 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 ...
1
vote
3answers
148 views

Keeping an eye on contention

In SQL Server, I am using the following command to see blocked sessions: select * from sys.sysprocesses where blocked>0 This is super. The problem is I need to see what block sessions there ...
1
vote
2answers
4k views

How do I determine why my stored procedure is getting deadlocked?

We have a stored procedure that our application uses to query data (no write operations are performed). I have the complete staging database copied to my local version of Sql Server developer edition. ...
1
vote
1answer
56 views

Deadlock scenario, where is this S lock coming from?

I am encountering the below deadlock scenario. Please see the attached object definitions and execution plans. The plans were pulled out of cache from a system where this deadlock does occur. I ...
1
vote
1answer
235 views

table partition in order to solve frequent deadlock issues - how would I know if it will work?

I use sql server 2005 enterprise edition and have a subscriber DB - part of a transactional replication - that is used for Business Intelligence purposes - they run reports out of it, and SSIS ...
1
vote
1answer
125 views

MySQL Latest Deadlock Explanation

Can someone explain this deadlock to me? It seems as if there are 2 inserts happening within milliseconds of each other with the same Primary Key. I'm not sure how this can cause a deadlock. At most a ...
1
vote
2answers
195 views

Changing two publications at the same time causes deadlock in distribution database

I have transactional replication setup. Let's say three databases on server A replicate to corresponding three databases on Server B. The databases are identical (same structure for different ...
1
vote
2answers
1k views

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 ...
1
vote
2answers
76 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 ...
1
vote
1answer
138 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 ...
1
vote
1answer
188 views

Deadlock detected on CREATE TABLE in PostgreSQL

I'm creating multiple tables asynchronously when I get deadlock detected. Both tables (Table A & B) have FK to one table (Table C) and I get deadlock on relation to Table C. Scripts CREATE TABLE ...
1
vote
1answer
9k 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? ...
1
vote
1answer
41 views

Clarification on mysql deadlock situation

Following deadlock is encountered while load testing a application. After going through MySQL documentation and other online resources what I figured out was that 1) Transaction (2) holds exclusive ...
1
vote
1answer
443 views

InnoDB deadlock with INSERT .. SELECT

I am trying to understand why a deadlock occurs when two workers in parallel are running INSERT .. SELECT queries on a table which has both 1) auto incremented primary key, 2) a unique index on ...
1
vote
1answer
142 views

Deadlock while updating rows and inserting new ones

I'm working with SQL Server 2012 Express Edition and I getting this error: Transaction (Process ID 53) was deadlocked on lock resources with another process and has been chosen as the deadlock ...
1
vote
1answer
258 views

TRUNCATE in transaction: dead lock

In a unittest we run this: BEGIN; TRUNCATE table1; TRUNCATE table2; ... UPDATE ...; ROLLBACK; Unfortunately this results in a dead lock if a cron job starts and this job operates on table1 and ...
1
vote
1answer
880 views

How does locking work in INSERT..ON DUPLICATE KEY UPDATE statements?

I am encountering deadlocks while trying to update multiple rows (a batch) using INSERT..ON DUPLICATE KEY UPDATE. Does MySQL lock all the rows in one batch or does it lock only the row it is updating ...
1
vote
1answer
261 views

DB2 Insert and Deadlocks

My application has 4 different threads doing inserts into the same DB2 table simultaneously. Could this cause a deadlock / lockwait situtation? Theoretically I don't see a problem here; as one ...
1
vote
2answers
890 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
1answer
237 views

apache hang on deadlock

i use code like this to prevent deadlock. while($retry<3 and $notsone) { try { $transaction->commit(); $notdone=false; } catch { $transaction->rollback(); $retry++; } } if ($retry==3) { ...
1
vote
1answer
317 views

Update and select concurrently running on same set of rows but different indexes are referred?

In multithreaded application where update and select can go simultaneously assuming update is used within transaction. If table has non clustered index and clustered index, what are the chances of ...
1
vote
1answer
59 views

Oracle Ref Partitioning: Deadlock due to child table row migration

My ordering application uses Oracle 11g Database. This DB has a primary table ORDERS and multiple child tables like ORDER_DETAILS, PLAN etc. ORDERS table is LIST partitioned on STATUS column and all ...
1
vote
0answers
88 views

MySQL - Preventing lock wait timeout when deleting rows from self

I have a table of around 500k rows (not big data), that I need to query against itself and then delete some of the rows which don't match the filters. At the moment my query looks like this: DELETE ...
1
vote
0answers
68 views

Why does this deadlock occur?

We're using MySQL with the INNODB storage engine. The account table is accessed by two different transactions. We didn't expect a deadlock because only one transaction is holding a lock (2): ...