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Full Stack JavaScript Techdegree Student 1,449 PointsWhat if I use ORDER BY?
First I just want to state that I totally understand how GROUP BY works. But still, I want to know clearly why when I used ORDER BY like this:
SELECT category, COUNT(*) AS product_count FROM products ORDER BY category;
the result came up this way:
category_____________________products_count
Books________________________29
Why only 1 row showed up? Where are the two other rows Clothing and Electronics? I did not use any query to leave those two categories out. This really baffled me. Please help!
1 Answer
ivana kantnerova
15,932 Pointsbecause there is no group by category, the aggregation function "count (*)" counts all rows of the table => the result has only one row .. it displays only the first category only because there is no other rows in results ... agregational function always returns only one value