NULL in SQL Server is not zero and not an empty string. It means the value is unknown, and that changes every comparison you write. Why equals never matches, the NOT IN trap that returns nothing, and where NULL is allowed to live.
SQL Server emergency? Email pinal@sqlauthority.com with URGENT in the subject line.
Testing an Application for SQL Injection
Testing an application for SQL injection on a safe copy reveals response clues and unsafe query construction before repair.
Collecting Server Facts Into One Table Every Night
Collect Server Facts each night to track SQL Server versions, settings, databases, and file sizes in a practical history table.
Replacing @@ERROR Checks With TRY CATCH in Old Procedures
Replace fragile @@ERROR checks with TRY CATCH, transaction state checks, and THROW while preserving clear failure information for callers.
SQL SERVER – Script/Function to Find Last Day of Month
A one line DATEADD query to find the last day of month for any date. It handles leap years: February 2008 gives the 29th and 2007 the 28th.
SQL SERVER – ASCII to Decimal and Decimal to ASCII Conversion
In this blog post we will see how we can convert ASCII to Decimal and Decimal to ASCII. In simple words, we will see the decimal and ASCII conversion.
SQL SERVER – Math Functions Available in SQL Server
One list of the Math Functions available in SQL Server, from ABS and CEILING to SQRT and TAN, and why RAND is the only nondeterministic one among them.
SQL Server slow? Let's fix it together in about four hours.
In my Comprehensive Database Performance Health Check, you share your screen, I guide you, and we fix your biggest performance troublemakers. No passwords. No remote access.
You keep every script, and the know-how to fix it yourself next time.
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My Practical Workshop has no PowerPoint, just live demos. My AI Enablement Workshop shows your team where AI saves hours, and where it quietly costs them.
Over 400 customers have worked with me this way, and not one shared a password. See all consulting options.
Who We Are
Pinal Dave is an SQL Server Performance Tuning Expert and independent consultant with over 24 years of hands-on experience. He holds a Masters of Science degree and numerous database certifications.
Pinal has authored 19 books and 125 Pluralsight courses. To freely share his knowledge and help others build their expertise, Pinal has also written more than 5,800 database tech articles on his blog at https://blog.sqlauthority.com.
Pinal is also a CrossFit Level 1 Trainer (CF-L1) and CrossFit Level 2 Trainer (CF-L2).
Nupur Dave is a social media enthusiast and an independent consultant. She primarily focuses on the database domain, helping clients build short and long-term multi-channel campaigns to drive leads for their sales pipeline.
Shaivi Pinalkumar Dave is a book author and a women’s artistic gymnast.

