For example, a null in the Price column of the ITEM table does not mean that the item is being given away for ... Nulls are one of the most misunderstood features of SQL database systems. Although ...

For example, a customer may have several ... You would use Is Null and Is Not Null in query expressions and SQL WHERE clauses. IsNull(), on the other hand, is a Visual Basic for Applications ...

For example ... you’re telling SQL to take a value and compare it against every value or set of values in a list using =. If any NULL values exist, a row will not be returned–even if both ...

To do this in SQL, you specify a column as NOT NULL. NOT NULL tells SQL to only allow a row to be added to a table if there is a value for the field. For example, NOT NULL assigned to the field ...