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May
18
2016

Index fun, disabling the Clustered Index

Following a conversation with my junior DBA, I decided to show you what happens when we disable indexes and in particular when we disable the clustered index for a…

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May
10
2016

Successful Anti-Patterns, Key Lookup VS RID Lookup

When it comes to technical subjects like databases, we must always look for proven solutions and best practices, which usually take us from A to B in the most efficient way. Usually. But what happens…

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Apr
15
2016

Back To Basics, Lock Escalation in SQL Server

Today at work we’ve had a very common request, no big deal, just a couple of UPDATE which affect tens of thousands of rows in a couple of tables independently. I can say I’ve been there, done that…

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Mar
14
2016

The Mysterious Case of the Missing Default Value

*First published @ www.SQLServerCentral.com (2015/12/01) Once upon a time, there was a DBA… yeah right! As probably like many SQL DBA’s, little by little I’m getting more curious about how SQL Server works internally. To…

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Mar
3
2016

Fast with values slow with variables

The other day I saw a thread on linkedin groups that was titled ‘Using Parameters in a Query is Killing Performance’, where the author…

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Feb
29
2016

Clustered index row order

One of the basic (and well used during interviews) questions about SQL Server internals is how you call a table without a clustered index, and that in SQL Server is called a HEAP….

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Feb
15
2016

Row compression, a bit of internals

Compression in SQL Server has been around for a while now, to be precise since SQL Server 2008, and comes in two different (complementary) flavors, ROW and PAGE compression. Unfortunately it’s only available in the Enterprise Edition (and Developer…

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Oct
28
2015

Daylight Savings end affects not only you, but your SQL Server too

The last weekend of October is a common date for the daylight savings (or summer time) to get to its end in the north hemisphere. According to Wikipedia: Daylight saving time (DST) or…

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Oct
10
2015

Steve Stedman’s DBCC Challenge, Week-7 Winning Solution

*First published @ Steve Stedman’s blog (2015/06/07) The seventh week of ten in the Database Corruption Challenge went well. There were a few new participants, and many of those who have competed week over week. The first to submit a correct answer this week was Raul…

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Oct
10
2015

Steve Stedman’s DBCC Challenge, Week-6 Winning Solution

*First published @ Steve Stedman’s blog (2015/05/27) If you are looking for more info on the corrupt database with Week 6 of the Database Corruption Challenge, you can take a look at the original post. Week 6 was won by Raul Gonzalez who submitted his…

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