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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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: ...
3
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3answers
598 views

Why am i getting deadlocks with 1 read and 1 write thread in SQL

if anyone could please help me understand why the following transactions deadlock? I am providing the 2 transactions and the indexes for each table: Transaction 1: SELECT blockId, blockData, ...
3
votes
1answer
738 views

Understanding SIX lock in Microsoft SQL-Server

Can somebody explain me how a process can acquire SIX lock on a page? I my deadlock-graph xml file I see that a process running under RC isolation level (executing a select statement at the moment of ...
3
votes
2answers
152 views

Deadlock with simple queries in sql server 2008

I have an application that must delete and insert registries from a table, the table is storing the historic registries for an access control and is stored with the datetime for the check in the ...
3
votes
1answer
736 views

Deadlocks on same wait resource

I am experiencing a deadlock in SQL Server, but I do not understand why this is a deadlock. It looks like the two resources are actually the same. Meaning that they each have the lock and are asking ...
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2answers
6k views

How to debug deadlocks in SQL Server 2008 R2?

I'm using SQL Server 2008 R2 that automatically lock database items based on my queries. Sometimes this deadlocks - two threads with different queries never ends. Is there any way to debug how SQL ...
3
votes
1answer
111 views

Optimizing concurrent updates in Postgres

I'm running concurrent Postgres queries like this: UPDATE foo SET bar = bar + 1 WHERE baz = 1234 Each query affects the fixed K number of rows, and I can't find a way to enforce the order in which ...
3
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2answers
358 views

Can 2 tables lock each other if concurrent read/update do not affect same rows? pagelocks off

Can 2 tables cause a deadlock, if the pagelocks are off, and the rows are not related. E.g. Query 1 runs for a few seconds Select * from Orders where CustomerID = 1 and DateOrdered between @D1 and ...
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1answer
116 views

Deadlock between two databases

I have my code running online shared hosting provider. Recently I am seeing too many deadlock exception is being thrown. As you know that shared hosting uses the same database server to host all the ...
3
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1answer
961 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
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1answer
4k views

Oracle 11g hunting down the deadlock, maybe foreign key?

I am trying to understand why a deadlock occurs in my database. The trace tells me that two updates on the same table are locking. In table is the first table to be written to in an transaction, only ...
3
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1answer
837 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 ...
3
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1answer
399 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
3k views

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
votes
1answer
1k views

SSIS package blocks itself if uses TRUNCATE

There is an SSIS package with Required transaction on the package level and Supported on the tasks level. The main part of the package is deleting the data and inserting new data: Here the Delete ...
3
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1answer
242 views

All-or-none exclusive lock on 2 SQL tables

My simplistic testing suggested that I can acquire an exclusive lock on 2 tables or postpone acquiring the lock on either until both can be acquired at once by using a query like this: SELECT ...
3
votes
2answers
839 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 ...
3
votes
1answer
3k 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 ...
3
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1answer
2k 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 ...
3
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0answers
45 views

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
278 views

Deadlock free MERGE-alike in MySQL?

I am trying to implement some parts of MERGE in the MySQL driver in Drupal. Of course, Drupal has something but in truth it only works because the most frequent MERGE issuer just eats exceptions. So, ...
2
votes
1answer
1k 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 ...
2
votes
2answers
746 views

SQL Server Deadlock Log Entries

We're analysing a deadlock situation on a SQL Server 2005 database and have set the trace flags 1204 and 1222. In the resulting logs we're seeing the following line repeatedly: "Log Viewer could not ...
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2answers
3k 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
votes
1answer
653 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 ...
2
votes
1answer
1k views

Why isn't the objectname and indexname populated in deadlock graph?

I got a request to check out some errors on a 2008 sp3 server (10.0.5500.0 - Enterprise Edition (64-bit)) and see if I could find deadlocks that were happening earlier. Traceflag 1222 wasn't enabled ...
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2answers
62 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" ?> - ...
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1answer
94 views

Avoiding Deadlocks

We currently have a trigger-based system in place that does the following: When records in certain tables are modified, a trigger fires that makes a field NULL in a varying number of records in ...
2
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1answer
261 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
407 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
215 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
146 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
1answer
1k 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 ...
2
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2answers
526 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
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1answer
240 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
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 ...
2
votes
2answers
133 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
928 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
542 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
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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 ...
2
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1answer
408 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
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0answers
161 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
2k 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
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0answers
326 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
370 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
171 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 ...
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2answers
981 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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1answer
777 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 ...
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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 ...
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1answer
2k 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 ...