SQL Tutorial
SQL Null Functions
Look at the following “Products” table:
| P_Id | ProductName | UnitPrice | UnitsInStock | UnitsOnOrder |
|---|---|---|---|---|
| 1 | Jarlsberg | 10.45 | 16 | 15 |
| 2 | Mascarpone | 32.56 | 23 | |
| 3 | Gorgonzola | 15.67 | 9 | 20 |
Assume that NULL values may be present in the optional “UnitsOnOrder” column.
Examine the SELECT statement that follows:
SELECT ProductName, UnitPrice * (UnitsInStock + UnitsOnOrder)
FROM Products;
The previous example’s outcome will be NULL if any of the “UnitsOnOrder” values are NULL.
