Controlling Transactions and Locks in SQL 2000 and 2005 - Part 2

In order for a transaction to meet the requirements of ACID, locks are employed to insure data integrity and multi-user access. The scope, or number of rows held by a lock, is referred to as Lock Granularity. This month, we will begin by introducing several different types of lock modes employed by MS SQL.

Regular Expression Transformation

The regular expression transformation exposes the power of regular expression matching within the pipeline. One or more columns can be selected, and for each column an individual expression can be applied. If all columns selected pass their tests then rows are passed down the successful match output. Rows that fail to pass all tests are directed down the alternate output.

Software patents: stupid or insane?

Lest the headline mislead you as to my biases, I consider software patents to be both stupid and insane. I raise this issue because it is currently rearing its ugly mug in the world of open source software, but it has affected much development in the proprietary worlds of Windows as well.

First of all, patent laws were created long ago, which is not to say the thinking was correct then either, but we have to recognize the intellectual and technological climate back then.

Living the "Least Privilege" Lifestyle: Don't Run Every Day Logged In

Don Kiely contends that exercising administrative rights over our computers is a major cause of insecure systems. In the first of five articles, he explains the concept of "least privilege" and shows why software developers should be happy to operate as "mere users."

So you want to be a DBA...

Written by an Oracle guy, but it's still some good advice for people that want to be DBAs. If you're experienced, pass it along to others that are looking to move into this role.

SQL database control and deployment

If you develop SQL databases, you know how difficult it can be to promote from the development environment to production with any level of confidence that the databases are the same.

When you have upgrades, it’s difficult to identify changes as well, especially when there are multiple developers making changes to multiple databases. The problem is compounded if your target environment is a client’s system over which you have no control. It’s staggering to think about what can happen if there are 600-plus client systems that have various versions of your database.

Finding Duplicate Indexes in Large SQL Server Databases

One important component of tuning a large, heavily used database, is to ensure that the tables are indexed optimally: enough indexing, but not too much indexing for the application you are running. There are rules of thumb about index tuning, but the entire issue is so complex that there's no "silver bullet" solution that will work for every case. However, in tuning indexes we can generally say that it's not a good idea to maintain duplicate indexes on the same data. SQL Server does not provide checks to prevent duplicate indexes from being created, as long as the names are different

Are UDFs Harmful to SQL Server Performance?

SQL Server 2000 introduced user-defined functions (UDFs), and they were immediately hailed as a great tool for encapsulating repetitive code, as well as allowing you to perform more complicated processing directly in an SQL expression. On its face, that claim is valid. You can certainly improve readability and maintainability with UDFs. But cleaner code will be cold comfort if your queries bog down and lock up your server.

How much backup is enough?

How much backup data should you keep around and what are the implications? Part 2 of a series looking at backups and their implications.

Executing the result set

SQL Server Database administrators often generate SQL Statements and execute the generated SQL statement in order to simplify certain tasks. It has always been a twin operation. This article illustrates how to use un-documented stored procedures to execute the generated SQL Statements directly.