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Welcome to my new blog.

My name is Paul Hewson and I work as a SQL DBA for a large insurance company in the UK. I have been working with SQL Server (almost) solidly since version 7 in 1999.

Having spent so much time learning from the large number of  fantastic blogs and websites out there I thought it was time to give something back to the DBA community by sharing hints and tips (snippets) that I have picked up over the years.

As this is brand new it is going to take me a little while to upload content so please be patient!

I hope that you find something useful here.



Popular posts from this blog

How to move the Microsoft Assessment and Planning Toolkit (MAP) database to a different drive

The Microsoft Assessment and Planning Toolkit (MAP) is a very useful tool for scanning your network to find instances of SQL Server plus all manner of detailed information about the installed product, OS and hardware it sits on.

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There is an issue with it the database it uses to store the data it collects, however. Assuming you don't have an instance called MAPS on your server, the product will install using LocalDB (a cut down version of SQL Server Express) and puts the databases on your C: drive. If you then scan a large network you could easily expand the database to 10GB which may cause issues on a server when that drive is often one of the smallest. However, there is a simple solution: connect to LocalDB using Management Studio, detach the databases, move to a different drive, set permissions on the new location if required and reattach the database. How do you connect to LocalDB? Here you go:

Connect to (localdb)\MAPTOOLKIT

The databases I move…

SAN performance testing using SQLIO

This document describes how to use Microsoft’s SQLIO to test disk/SAN performance. It is biased towards SQL Server – which uses primarily 64KB and 8KB data pages so I am running the tests using those cluster sizes, however, other sizes can be specified.  Download SQLIO from SQLIO is a command line tool with no GUI so you need to open a command prompt at C:\Program Files (x86)\SQLIO after you have installed it. Configuration First of all edit param.txt so that you create the test file we will be using. The file needs to be bigger than the combined RAID and on-board disk caches. In this case we are using a 50GB file.
The “2” refers to the number of threads to use when testing, you don’t need to change this now. The “0x0” value indicates that all CPUs should be used, which you probably don’t want to change either, “#” is a comment. The only part you may want to change is 51200 (50GB) and the drive letter. After …

How to configure the SSAS service to use a Domain Account

NB Updating SPNs in AD is not for the faint hearted plus I got inconsistent results from different servers. Do so at your own risk! If you need the SSAS account on a SQL Server to use a domain account rather than the local “virtual” account “NT Service\MSSQLServerOLAPService”. You may think you just give the account login permissions to the server, perhaps give it sysadmin SQL permissions too. However, if you try and connect to SSAS remotely you may get this error:

Authentication failed. (Microsoft.AnalysisService.AdomdClient) The target principal name is incorrect (Microsoft.AnalysisService.AdomdClient)

From Microsoft: “A Service Principle Name (SPN) uniquely identifies a service instance in an Active Directory domain when Kerberos is used to mutually authenticate client and service identities. An SPN is associated with the logon account under which the service instance runs. For client applications connecting to Analysis Services via Kerberos authentication, the Analysis Services clien…