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12 September 2011 20:52

Table Variables and Parallel Plans

I’m sure somewhere there must be carved into the side of a mountain those immortal words “ Well it seemed a good idea at the time!” ( with due homage to HHGTTG ) Hopefully there’s nothing in this post which you the reader will not know about already?...
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05 September 2011 13:23

Posts of Interest

I don't make a habit of just posting links as I think it's like a form of cheating, however sometimes there are things I want to keep track of and I know If I put the link on my blog I'll find it again! so: a short one here; We've just...
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14 September 2010 22:08

IF Exits vs Count(*) – just when you thought it was safe ….

Here’s a couple more of the topics I covered in my presentation “ Gone in 60 Nano seconds “.  It’s tricky sometimes formatting posts to display correctly on the blog so for most of the material from the presentation I’m going to link to the pages...
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09 September 2010 22:25

Don’t add that column

This is the first of the topics from my presentation “ Gone in 60 nano seconds “   As a quick summary this is why additional columns can cause degraded performance. Background I put this brief list of points together after having a carefully tuned...
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28 July 2010 13:28

An interesting annecdote

A while ago I blogged about using the dmvs to identify lookups and scans on tables http://sqlblogcasts.com/blogs/grumpyolddba/archive/2010/05/19/analysing-indexes-reducing-scans.aspx Well continuing on from this I had discovered that two of the top scanning...
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16 June 2010 20:15

So which null equals this null, that null? maybe this null, or is it this null?

Tuning takes many routes and I get into some interesting situations and often make some exciting finds, see http://sqlblogcasts.com/blogs/grumpyolddba/archive/2010/05/17/just-when-you-thought-it-was-safe.aspx for an example. Today I encountered a multitude...
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04 June 2010 12:04

Given the choice 8 out of 10 Optimisers prefer.........

Did you know that included columns do not partake in the uniqueness of a unique index? ( see below ) A few months ago we upgraded our major production system from SQL2000 to SQL2008, this has allowed me to apply some of the index tuning techniques I devised...
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06 April 2010 21:02

Would you expect this error ?

Now I know why, but what I'm thinking is that if I create an error should I get valid data returned? To explain, I was browsing through the dmvs for queries which might benefit from tuning and I identified a query with two clustered index scans (...
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23 March 2010 19:33

Cursors 1 Sets 0

I had an interesting experience with a database I essentially know nothing about. On the server is a database which stores session state, Microsoft provide the code/database with their dot net, so I'm told. Anyway this database has sat happily on...
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18 February 2010 15:56

If you have Enterprise Servers you should read this blog

I feel that a DBA should have a good working understanding of the underlying server that SQL Server sits upon and the storage system(s) that it connects to, otherwise you may not know if you're being spun a yarn when you're trying to understand...
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