COUNT(*) ≠ COUNT(column) 🧮 Many SQL users assume both do the same — but they don’t. --- 🔹 What’s the difference? COUNT(*) Counts all rows in the table Includes rows with NULL values COUNT(column) Counts only non-NULL values in that column Rows with NULL in the column are ignored --- 📌 Example insight If a table has 5 rows but only 3 rows contain a value in a column, then: COUNT(*) → 5 COUNT(column) → 3 --- 💡 Key takeaway: Use COUNT(*) when you want total rows. Use COUNT(column) when you care
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