Developer hearted / Relational minded : T-SQL

Cannot find the source of a SQL Server error ?

Jens K. Suessmeyer — Fri, 25 Sep 2009 11:33:24 GMT

Ever had an error in your application and you couldn't find the source of all evil and where the error is thrown at the end ? Well, SQL Server profiler does a great job about that, but you really need to understand which events to filter for and how to...(read more)

Database Programming: Did You Know IN Can Do This?

Jens K. Suessmeyer — Sun, 06 Sep 2009 19:50:08 GMT

Ward Pond , one of the marvelous SQL geeks within Microsoft published a nice thing wich we had a discussion internally on concerning the capabilities of the IN operator: http://blogs.technet.com/wardpond/archive/2009/09/04/database-programming-did-you-know-in-can-do-this.aspx...(read more)

Light weight SQL Server procedure auditing without using SQL Server auditing

Jens K. Suessmeyer — Mon, 08 Jun 2009 22:50:00 GMT

A week ago a colleague asked for different options to do audit stored procedure calls. With his allowance I will post the question here. “The applications used at the customer site all access these databases using stored procedures ( only , as far as...(read more)

The “magic” about trustable relationships with NULL and NOT IN

Jens K. Suessmeyer — Mon, 25 May 2009 22:52:27 GMT

As a follow-up to my former post “ Why you shouldn't´trust the friendship of NULL and the (NOT) IN predicate ” I asked Paul Randal during our SQL Server Master training about the possible internal reason that the results can vary if you have NULL...(read more)

A long (but not missed) friend revisited, prefixing stored procedures with SP_

Jens K. Suessmeyer — Tue, 28 Apr 2009 09:59:56 GMT

Coming as a simple sample with PBM (creating a policy with a condition that procedure names shouldn't´t start with SP_) and getting an interesting question in one of my classes, I wanted to revisit the question about the yet in some places existing naming...(read more)

When is random “random enough” ?

Jens K. Suessmeyer — Wed, 08 Apr 2009 10:19:00 GMT

An interesting question came up in a private conversation. If you want to pick a random value from a random generated result set and want to make sure that the row is really random, is the known ORDER BY NEWID() really random enough ? The point is that...(read more)

Why you shouldn't´trust the friendship of NULL and the (NOT) IN predicate

Jens K. Suessmeyer — Sat, 07 Mar 2009 10:33:00 GMT

A colleague had a problem concerning a query using the (NOT) IN predicate, use the following table creation script (attached to the blog entry) to see the effects of the problem and to repro it on your machine. Imagine you have two tables (not that hard...(read more)

Determine the current status of a SQL Server Agent job

Jens K. Suessmeyer — Fri, 09 Jan 2009 00:36:00 GMT

Due to the problem that there is no definite table for getting information about the current status of jobs, I created a small procedure grabbing the information from parts of the internal procedures used to extract the very relevant information. As an...(read more)

Tedious trigger generation getting simplified

Jens K. Suessmeyer — Thu, 08 Jan 2009 14:50:00 GMT

While talking with a former colleague of mine, we were elaborating about methods for syncing databases in his company. After boiling down the scenario to a point where we excluded all sync technologies possible, we came down to good old triggers. As of...(read more)

Merge it your own way -- Followup on the test

Jens K. Suessmeyer — Tue, 29 Jul 2008 04:04:35 GMT

After publishing the first test results on a previous post I got in contact with the product team to followup the test results. After redoing the test on real hardware and in a client - server scenario, the following result could be extracted from...(read more)

Get all system databases of a server

Jens K. Suessmeyer — Wed, 16 Jul 2008 13:06:00 GMT

The easiest way for querying all system databases of a server is to assume that databases create by a user come with a database_id >= 5 in sys.databases. But the problem is that distribution databsaes will not be kept into this consideration. Therefore...(read more)

Obfuscation is not a security feature – Spoofing the APP_NAME

Jens K. Suessmeyer — Tue, 06 May 2008 11:00:00 GMT

SQL Server 2005 introduced an interesting and long demanded feature, the LOGON triggers. First only defined via server event triggers, it has become more and more popular in same scenarios to prevent users with a certain machine environment accessing...(read more)

Merge it your own way - Comparison of SQLAdapter vs. SQLCommand vs. MERGE

Jens K. Suessmeyer — Sun, 04 May 2008 10:14:00 GMT

The question which always comes up in my sessions about SQL Server 2008 is according to my most loved feature in SQL Server 2008, the MERGE command. People always ask me how the performance comparison with MERGE is compared to some standard / traditional...(read more)