I recently had a need to monitor inserts against a particular table in order to determine what kind of locks they were acquiring. Being that we could not run traces on the system, I had to resort to a roll-your-own approach to monitoring the table. The goal was to determine what kind of locking was [...]
Archive of posts filed under the Troubleshooting category.
Execution Plans
The execution plans SQL Server creates and uses is a huge topic with many intricacies. Now I have never spoken to anyone on the SQL Server Development team, however I would imagine that there are some extremely sharp people in the query optimization team. In a nutshell, this is where the magic happens in SQL [...]
Understanding SQL Server Deadlocks
In order to fix deadlocks, it’s critical to understand why they occur. I’ve gotten some push back sometimes from readers when I write articles that do not give cookie cutter solutions, but the “teach a man to fish” adage couldn’t be more true for deadlocks. All of it revolves around locking, which is a central [...]
The object name ‘x’ contains more than the maximum number of prefixes. The maximum is 2.
This error usually comes up when you are trying to perform a SELECT..INTO across a linked server. The problem is that a 4 part name cannot be used as the “INTO” parameter. This will fail: SELECT * INTO [remoteserver].RemoteDB.dbo.sysdtspackages FROM MSDB.dbo.sysdtspackages The trick is to create the table on the remote server, then perform an [...]
The EXECUTE permission was denied on the object
This error is pretty self explanatory. If you are here, I’m sure you simply want to know how to correct it, so here goes. The user context in which you are executing does not have the rights to execute the procedure or function. So first, in order to find out which user you are, simply [...]
String or binary data would be truncated.
This error message is relatively straight forward. The way it normally happens is when you are trying to insert data from a table that contains values that have larger data lengths than the table you are trying to insert into. An example of this would be trying to insert data from a permanent table, into [...]
Troubleshooting SQL Server Slowness
The first step in diagnosing SQL Server Slowness is to determine the physical bottleneck with the most contention. Contention in one of the following areas does not always mean that subsystem is performing poorly. It could just as well be improper utilization due to poor tuning. Nevertheless, identifying the bottleneck is always the first place [...]
Performance Counters
The following list of performance counters have been modified to include the most pertinent in identifying the bottleneck of your system. This list is for reference purposes. If needing to troubleshoot slowness read troubleshooting sql server slowness. Memory Object: – Memory Counter: – Available Mbytes Preferred Value: – > 2000MB Description: With 64 bit OS’s [...]
Blocking Processes (lead blocker)
SELECT
spid
,status
,loginame = SUBSTRING(loginame, 1, 12)
,hostname = SUBSTRING(hostname, 1, 12)
,blk = CONVERT(char(3), blocked)
,open_tran
,dbname = SUBSTRING(DB_NAME(dbid),1,10)
,cmd
,waittype
,waittime
,last_batch
FROM master.dbo.sysprocesses
WHERE spid IN (SELECT blocked FROM master.dbo.sysprocesses)
AND blocked = 0
Turn On Deadlock Trace Flag
DBCC TRACEON (1204, -1)
