Translate CONNECT BY into recursive CTEs with root selection, depth, paths, sibling ordering, cycle checks, and a recursion limit.
SQL Server emergency? Email pinal@sqlauthority.com with URGENT in the subject line.
SQL SERVER – Case Sensitive Database and Database User – Fix: Error: 15151 – Cannot find the user , because it does not exist or you do not have permission.
Jeff hit Error 15151, cannot find the user, even though the user existed. The cause was a case sensitive database, and here is the fix.
SQL SERVER – Solution Part 2 – A Quick Puzzle on SQL JOIN and NULL – SQL Brain Teaser
Part 2 of the solution to my puzzle on SQL Join and NULL. Readers still email me answers every day, so here are more of the good ones they sent.
Numbers Table vs GENERATE_SERIES: Building Rows on Demand
Learn numbers table in SQL Server with practical examples, clear checks, common traps, and guidance for your own database.
T-SQL Errors and Reactions in SQL Server: SQL in Sixty Seconds #002
T-SQL errors and reactions are the subject of this early SQL in Sixty Seconds episode with Rick Morelan. The tests here show which errors stop one statement, which stop the whole batch, and how XACT_ABORT, TRY CATCH and THROW change the reaction.
What Is Big Data? A Simple Explanation for Database People
What Is Big Data? It is the point where data outgrows one machine, and the fix is to scale out. This post explains the failures of one server and walks through 40 TB split across 8 nodes.
Reading Fixed-Width Text Files With OPENROWSET and a Format File
Read fixed-width text files with OPENROWSET and an XML format file, trim fields, validate conversions, and load only acceptable rows.
SQL Server slow? Let's fix it together in about four hours.
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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.

