Introduction"I want to list customers who haven't ordered, but I get zero results," or "The count doesn't match when I ...

For those new to data analysis, I will explain how to handle NULL (empty fields), where mistakes are most common in SQL, using concrete examples and results. Understanding NULL will help you solve ...

Don’t let Null values derail your formulas. See how to use the NZ function to convert the values to zeroes. You’ve created a query that calculates an invoice total by adding the order total and the ...