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Your JOIN Is Correct. Your Data Grain Isn’t.
SQL Server - JOINs & Data Grain
4 min read

Your JOIN Is Correct. Your Data Grain Isn’t.

My Table Has 3,200 Accounts. Why Did This JOIN Return 7,841 Rows?

Dan Griffin · Sep 28, 2026

Can HAVING Work Without GROUP BY in SQL Server? (Yes, Here's Why)
SQL Server - Aggregation & Filtering
3 min read

Can HAVING Work Without GROUP BY in SQL Server? (Yes, Here's Why)

Most SQL analysts learn to use HAVING with GROUP BY. But SQL Server doesn't always need both. Discover how implicit aggregation works, when to skip GROUP BY, and why it matters for real-world queries.

Dan Griffin · Jul 10, 2026

SQL GROUP BY Multiple Columns: Think in Result Grain
SQL Tips
3 min read

SQL GROUP BY Multiple Columns: Think in Result Grain

Learn how SQL Server groups unique column combinations using a practical Region + SalesChannel revenue example.

Dan Griffin · Feb 10, 2026