I have two tables:
- Product (PK product_id, brand, model)
- Order (PK invoice_id, customer_name, customer_email, FK product_id)
I am trying to find the product(s) whose number of times that product is sold is closest to the average number of times a product is sold.
The problem is as far as I know the AVG
function ignores NULL values when it calculates the average. So if a product has never been sold before, it won't be included in the average, but it should be included for my calculation to be correct. A null should be counted as zero to lower the average.
How can I work around this?
Best Answer
To count
NULL
like 0 when calculating an average, usecoalesce
will return the first of its arguments that is notNULL
.