Which statement best describes the NULL function's purpose?

The NULL function's purpose is to generate empty references for use in expressions. In many programming and database contexts, a NULL value denotes the absence of a value or a non-existent reference, making it useful for creating placeholders in your calculations or data manipulations. This allows developers to handle scenarios where data might not be available or defined, enabling them to construct more robust and error-tolerant applications.

Using NULL effectively can help prevent errors in expressions that expect a value; instead of causing a failure, the presence of a NULL can be accounted for, allowing for conditional logic to manage situations where data may be missing. For instance, when performing calculations or comparisons, NULL can be used to signify that there is no data to operate on, thus enabling the logic to proceed without breaking.

In contrast, the other options relate to different functionalities entirely: creating new records, discarding invalid entries, or counting records, none of which are aligned with the intrinsic role of the NULL function.