![]() ![]() I ran PerfMon with all counters that seemed relevant (Network related, Available threads, Available Work Items, Log Buffer Waits as well as the usual ones such as Processor & memory related) but there was nothing immediately obvious. Otherwise they get shared locks, and when they simultaneously try to upgrade to exclusive locks, they deadlock. In SQL Server, if you issue the selects with WITH (UPDLOCK), the second select will wait until the first select is finished. two select-insert pairs running in parallel. Most of the articles that I have read are related to transactions and queries and therefore locks related to data pages/tables but not many related to memory/threads/buffer resources. Its very useful if you have deadlocks involving e.g. ![]() Turning on Trace Flag 1222 provides information that is next to useless (log records below). So I am presuming it is not due to DML statements. The error occurs about once a week on differing days and at different points in the data load process. And as MatBailie says, 2 processes are required for a deadlock, because locks (which result in deadlocks) are at the process level. Definitely don't start trying to solve a deadlock you're not even sure is a deadlock. There are no other DML statements running simultaneously. Deadlocks are stored in the health monitoring tables, so you can query them to find out if you really had one. This is an overnight job which effectively loads a reporting database and performs various corrections to the data. Transaction (Process ID 52) was deadlocked on thread | communication buffer resources with another process and has been chosen as the deadlock victim. Recreating the SQL Server Deadlock Let's start with creating two tables. The only link, to me, seems to be from this indexed view which is why I've included it. What is unclear to me is why SP1 is wanting a lock on the IXfollow-memberidincludes index. We will create some tables and then use transactions to insert some new data. The deadlock appears to be happening on the last line of each query (the inserts). We have a SQL Job (2005) that from time to time will fail due a deadlock. Solution To demonstrate how the SQL Server deadlocks occurred I am going to create two separate active transactions opened in two connection windows. 3,247 2 17 54 Indexes can help reduce the number of deadlocks but bear in mind that the transaction isolation level will also dictate the number of deadlocks that you get. ![]()
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