SQL AVG function
Here is a clear, practical guide to the SQL AVG function, including behavior with NULLs, examples, and best practices.
✅ What SQL AVG function Does
AVG() returns the average (mean) of all non-NULL numeric values in a column.
✅ Basic Syntax
📌 Basic Examples
1. Average salary
2. Average product price
🔥 AVG with WHERE (filter rows first)
🔥 AVG with GROUP BY (averages per category)
🧠 Important Behavior Notes
✔ AVG() ignores NULL values
✔ Returns NULL if all values are NULL
✔ Works only on numeric columns
✔ Often paired with GROUP BY for summary analytics
