>Hi Mike,
>
>Yes, actually in this case it matters. My client's software collects lab test values, and they need to distinquish between zero and nothing entered. Some of their lab values can range from an inputted zero to something else. Blank would just indicate that they received no data for that particular test. I'm in fact using ISBLANK() to make that distinction. Some of their test ranges consider zero as being an abnormal value, so I need to make the distinction.
>
>I played around with using NULL, but it had some weird side effects in the results of my report programming. I could have gotten around that, but it's easier just to use BLANK AND ISBLANK(). Also, I'm sure that NULL would confuse my client, more than it would be helpful. I was wondering if there was a keyboard shortcut for turning a field blank, instead of needing to use code with the BLANK command. Kind of like the "Ctrl 0" for Null. But, I guess that doesn't exist, so I'm going to put some code into the rightclick event to blank out the field.
>
>The annoying thing is that the field is initially blank, but you cannot manually blank it out after you type into the field. Zero doesn't appear initially, but will always appear after you've inputted into that particular field for that record (unless you program a blank routine for it). Oh well.
>
>Dave
>
>>>I need to provide an easy way for users to blank out a numerical field that contains previous input. VFP won't allow one to just delete the field's value, which I don't understand why. When I attempt to delete the value from the field, the field automatially resets itself to zero. I don't want to use null values for practical reasons.
>>
>>Well, even when the field is blank it is equal to 0. Does it really matter whats shown? Anyways, you can get rid of the 0 by doing a BLANK on the field. I think the only time its truly relevent, however, is if you have logic that uses IsBlank() on the field.

You can use BLANK, of course. But please consider:

.NULL. values are the most logical way to represent missing information, and it is precisely toward this purpose that .NULL. values were introduced in VFP.

There is a built-in shortcut key to NULL a value.

You can display NULL values to the end-user in any way you like. For instance, SET NULLDISPLAY TO "???" will show three question marks for missing data.

With nvl(), you can convert null values to other values. For instance, change missing data to 0 for a certain calculation.

What other problems did you have with NULL values?

Hilmar.

Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)