Checking for Null values

[tjcusick]

Is it necessary to check for a null value if you are reading the value from a field in as a Float?

fcurrCS  := qryBOPDetailCREDIT_SCORE.AsFloat;

I've tested it and when ever the field is null in the table the variable comes back as a zero.

What would be the correct programming answer?

Ideas/suggestions?

Tom C

 

[TonHu]

Questions:
Do you _need_ to know whether it's null? (what's wrong with it being 0?)
or do you try to avoid possible exceptions? (Answ.: No, it returns 0 so there's no 'danger')

HTH
TonHu

 

[roo0047]

The "correct" answer is that "null has no value", where "zero" is a value.

If field = null then //it hasn't been filled.

If field = 0 then //it's been filled as zero.

A Null field.AsFloat will always return 0.

A Null numeric field.AsString will always return ''.

A zero filled numeric field.AsString will always return '0'.

Those all look like differences to me!

Roo
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