Can we have a NULL value in primary key columns? No. The primary key has to uniquely identify each row, and NULL cannot do that. Here is why.
SQL Server emergency? Email pinal@sqlauthority.com with URGENT in the subject line.
SQL SERVER – FIX – Linked Server Error 7399 Invalid authorization specification
Creating a linked server with just a server name can fail with Error 7399, Invalid authorization specification. Why the Linked Server test fails and the fix.
Changing a User-Defined Table Type That Procedures Use
You need one more column in a table type, but procedures depend on it. Here is the order of moves that works, with the errors along the way.
SQL SERVER 2016 – How to Use SQL Server 2016 – Stretch Database – Notes from the Field #127
Kenneth Urena shows how to use Stretch Database, the SQL Server 2016 feature that moves cold table data to Azure while your queries keep working.
SQL SERVER – System Objects Not Visible in SQL Server Management Studio
Why were system objects not visible in SSMS 2016 when SSMS 2014 showed them on the same instance? A client asked me, and here is the answer.
SQL SERVER – How Much Free Space I Have in My Database?
Free Space inside data files differs from unused space on the Windows volume. I check both when planning growth.
SQL SERVER – Vertical Select Mode feature in SQL Server Management Studio
Balmukund showed me the Vertical Select Mode in SSMS: hold ALT, select a block, then type on every row at once. It works in SQL Server 2012 and later.
SQL Server slow? Let's fix it together in about four hours.
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You keep every script, and the know-how to fix it yourself next time.
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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.

