Error 8117 appears when you SUM a BIT column, because bit is invalid for sum operator. I reproduce it with a small table and show a simple workaround.
SQL Server emergency? Email pinal@sqlauthority.com with URGENT in the subject line.
SQLAuthority News – Learning Never Ends – Becoming Student Again
Learning should never stop. Visiting a friend’s new training center got me thinking about Becoming Student again, and why I keep learning even from old material.
SQL SERVER – Beginning of SQL Server Security
The beginning of SQL Server security: how authentication, logins, users and permissions work together to keep your data safe from misuse.
SQL Server Pitfalls: Five Short Lessons With the Fix for Each
SQL Server pitfalls start with a small assumption. This page shows five of them, one for each topic: query hints, errors, permissions, XML and recursive queries. Each lesson shows the mistake first and the tested fix second. Every result comes from SQL Server 2025.
What Distributed SQL Means and What It Costs
Understand distributed SQL through data placement, compute and storage roles, write coordination, and the latency and operating costs behind scale.
What Is a Cursor in SQL Server, and When to Avoid One
A cursor in SQL Server took 260 milliseconds where one SELECT took 4. Why the gap exists, how to turn a loop back into a set, and the three cases where a cursor really is the right answer.
Upcoming Birthdays in the Next 30 Days With T-SQL
Find upcoming birthdays with T-SQL across year boundaries, choose a February 29 policy, and build a clear next-30-days list.
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