Wednesday, 9 March 2016

SQL Server Analysis Services Error: The following system error occurred: (Microsoft.AnalysisServices)

Clearly, while adding some users as Windows Administrators, not only do we do that, but also we add them as Administrator of Analysis Services (SSAS). So, if we delete them from Windows then they will become orphaned users inside SSAS. As a result of this action, not surprisingly, we are going to get the following error when we are trying to add other users to the server administrator role in SSAS via the GUI or by code.

“The following system error occurred: (Microsoft.AnalysisServices)”

This sort of error is raised at times as the orphaned users have not got a correct matching inside the Active Directory. So, only their invalid user IDs will still be registered.



What we should do to fix this issue and be able to add other users is, firstly, to remove these orphaned users and, finally, add the new ones. I hope you find this short post interesting. Thanks for reading!

Friday, 4 March 2016

How to split the tempdb database into more files

Naturally, as DBAs we do know is mandatory to modify data and log properties of the tempdb database. Unless we do a customized configuration of it, SQL Server will create only one data file and log file by default. The reality is that we will mostly need to create more files on production environments. There are many recommendations not only about how to create them but also the quantity of files on OLTP environments. To be perfectly honest, I do not believe that the number of data files only depends on the number of cores, but it also depends on concurrency, tempdb contention issues, the workloads on your server and, clearly, the performance of your queries. So, there is no a rule for it. Moreover, depending on the SQL Server version we are working on, we may NOT need to split the tempdb into many data files. There are some situations where it will work splendidly with only one data file since each database environment is unique and, therefore, we need to determine the best for it.

Today we are not going to discuss more details about it. I just would like to suggest splitting your tempdb database into four data files (if you have four or eight core) or eight data files (for 16, 32, 64, or more cores) and ONLY one log file. Ideally, we also need to locate them in different drives RAID1, RAID5 or RAID10. Now having very clear the situation, I will show you one small script to split your default tempdb database into 8 data files and remaining the only one log file.

USE [master]
GO
ALTER DATABASE [tempdb] MODIFY FILE (NAME=N'templog', NEWNAME= N'tempdev_Log')
GO
ALTER DATABASE [tempdb] MODIFY FILE (NAME=N'tempdev', NEWNAME=N'tempdev_Data01')
GO
ALTER DATABASE [tempdb] MODIFY FILE (NAME=N'tempdev_Log',  FILENAME= N'D:SQLTempDBtempdev_Log.ldf', SIZE = 2048MB , FILEGROWTH = 2048MB)
GO
ALTER DATABASE [tempdb] MODIFY FILE (NAME=N'tempdev_Data01',  FILENAME= N'D:SQLTempDBtempdev_Data01.mdf', SIZE = 512MB , FILEGROWTH = 1024MB )
GO
ALTER DATABASE [tempdb] ADD FILE ( NAME = N'tempdev_Data02', FILENAME = N'D:SQLTempDBtempdev_Data02.ndf' , SIZE = 512MB , FILEGROWTH = 1024MB )
GO
ALTER DATABASE [tempdb] ADD FILE ( NAME = N'tempdev_Data03', FILENAME = N'D:SQLTempDBtempdev_Data03.ndf' , SIZE = 512MB , FILEGROWTH = 1024MB )
GO
ALTER DATABASE [tempdb] ADD FILE ( NAME = N'tempdev_Data04', FILENAME = N'D:SQLTempDBtempdev_Data04.ndf' , SIZE = 512MB , FILEGROWTH = 1024MB )
GO
ALTER DATABASE [tempdb] ADD FILE ( NAME = N'tempdev_Data05', FILENAME = N'D:SQLTempDBtempdev_Data05.ndf' , SIZE = 512MB , FILEGROWTH = 1024MB )
GO
ALTER DATABASE [tempdb] ADD FILE ( NAME = N'tempdev_Data06', FILENAME = N'D:SQLTempDBtempdev_Data06.ndf' , SIZE = 512MB , FILEGROWTH = 1024MB )
GO
ALTER DATABASE [tempdb] ADD FILE ( NAME = N'tempdev_Data07', FILENAME = N'D:SQLTempDBtempdev_Data07.ndf' , SIZE = 512MB , FILEGROWTH = 1024MB )
GO
ALTER DATABASE [tempdb] ADD FILE ( NAME = N'tempdev_Data08', FILENAME = N'D:SQLTempDBtempdev_Data08.ndf' , SIZE = 512MB , FILEGROWTH = 1024MB )

After having successfully executed, we must restart the database engine in order to get the new files created and all changes done. I hope you find this post interesting. Let me know any remark if you may have. Thanks for reading!
HELLO, I'M PERCY REYES! I've been working as a senior SQL Server Database Engineer for over 20 years; I'm a three-time Microsoft Data Platform MVP. I'm a cryptographer conducting research on cryptographic Boolean functions and their applications.