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Putting a column name in a COUNT() function may not always give you what you are looking for.  Read more...

ETL ( Extract, transform, load) doesn't have to be like a spell on hell. To make a success of ETL systems, you need the freedom and ability to make graceful U-turns when you detect a mistake in architecture or configuration: to fix the root problem rather than to merely tackle the symptoms. Feodor lists the eight most common root causes of failure in ETL systems, and how to fix them.  Read more...

Database ownership is an old topic for SQL Server pro's. Check this simple lab to learn the risks your databases can be exposed to.  Read more...

In data mining, we sometimes need to perform techniques such as Z-score normalization on numeric data type columns to prevent one column from skewing or dominating the models produced by the machine learning algorithms. Dallas Snider explains how to perform this in SQL Server with T-SQL code.  Read more...

The APPLY operator allows you to join a record set with a function, and apply the function to every qualifying row of the table (or view). The APPLY operator takes on two formats: CROSS APPLY, or OUTER APPLY. This article will explain the differences between these two formats, and show you examples of how each of these formats work.  Read more...

Dynamic Management Views (DMVs) are a significant and valuable addition to the DBA's troubleshooting armory, laying bare previously unavailable information regarding the under-the-covers activity of your database sessions and transactions.  Read more...

If you can examine and understand execution plans, you can achieve better understanding of the database system and you will write better database code. Grant Fritchey shows you how.  Read more...

In this chapter we will talk about security recommendations for SQL Server Data Mining.  Read more...

Grant Fritchey reviews Midnight DBA's Minion Reindex, a highly customizable set of scripts that take on the task of rebuilding and reorganizing your indexes.   Read more...

The easiest way to determine if there is encrypted data in a database is to get that information from whoever wrote the application. Aside from that, there are a few things you can look for which would suggest that you have encrypted data in a given database.  Read more...