Null Value Handling

Visual FoxPro provides support for null values. This support simplifies the task of representing unknown data and makes it easier to work with Microsoft Access or SQL databases that may contain null values.

Null values are:

  • Equal to the absence of any value.

  • Different than zero, the empty string (""), or blank.

  • Sorted ahead of other data.

  • Propagated in calculations and most functions.

Null values affect the behavior of commands and functions, logical expressions, and parameters.

Visual FoxPro support for null values complies with ANSI standards and affects any area of the product where values and expressions are used.

To use null values in See

Commands and functions

Behavior of Null Values in Commands and Functions


Behavior of Null Values in Logical Expressions


NULL as a Parameter

Expand imageUsing NULL in Values and Expressions

Expand imageSee Also

© , 1996-2020 • Updated: 11/10/20
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