Null Vales

Jack des Bouillons (7/1/08 9:49AM)
Roger (7/1/08 7:40PM)


Jack des Bouillons (7/1/08 9:49 AM)

That's the only type I've seen where there are problems...

Because it is possible to CREATE a NAN (null) in a numeric field by
dividing

by zero...

Which is why, btw, that I wrap all calculations where division is used:

[Table]NumbericField:=NUM_Divide(Value1;$Value2)

Within NUM_Divide, I check to see if the second value passed is 0, and
if it

is, return 0 rather than running the calculation.

Jack des Bouillons

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On 7/1/08 9:33 AM, "Roger" <roger@... wrote:

Is it only a problem with numerical fields?

Roger

Jack des Bouillons wrote:

Oh yes it DOES bother 4D...

A NULL value in a numeric field, for example, can screw up the use of
SUM,

AVE, Subtotal, etc.

Null values mean you have a damaged data file, and it should be
repaired.

Check out DataToolsÂ&Aring; by Committed Software.

Roger (7/1/08 7:40 PM)

I think that this is more likely than the divide by zero

It is a field that was added to the database - although some time age.

These could be old records.

When I get the data fixed I can investigate some more

I tried assigning each field to itself, but that didn't work. I have
now

written a routine to go through the records and this routine will
allow

me to get a list of records changes

Thanks

Roger

jerome pupier wrote:

Hi,

Maybe you have just added a field to the table.. In that case, the
value is

Null, because records have not been re-written, and they are set to
default

the first time 4D reads/writes them. You may try to do an apply to
selection

to force rewrite of records.

APPLY TO SELECTION([Table];[Table]AnyField:=[Table]Field)

Hope this will helps

Amicalement,

J&Egrave;r&Ugrave;me

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Summary created 7/1/08 at 5:25PM by Intellex Corporation

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