Add SQL’s Not operator to find values that aren’t Null. Using Northwind, the sample database that comes with Access, I will create a few queries to illustrate using Is Null and Is Not Null.

On the surface, it may appear that the SQL clauses IN and EXISTS are interchangeable. However, they’re quite different in how they handle NULL values and may give different results. The problem ...

Suppressing null values results in a null value being represented by a one-byte empty field indicator. The null value itself is not stored. Knowing whether a data field allows null values assists you ...

One of the trickier aspects of application development is dealing with null or nonexistent data. Tony Patton takes a closer look at null values in the .NET framework.

Learn to change the default behavior and return HTTP 404 when action methods in ASP.NET Core return null values.