Is zero the same as empty?

[Peter Haworth]

I ran across one situation involving zero/empty a while back that I
reported as a bug, not sure if it's been fixed or not.

If you INSERT a row into an SQL database and leave out some of the columns,
those columns end up as NULL in the database (assuming they don't have a
default value assigned in the schema).  If you then issue a SELECT
including one of those columns and it has a numeric data type in the
schema, it comes back as zero, not empty or NULL.  That made it impossible
to distinguish between an "uninitialized" value for the column and a zero
value.

Pete
lcSQL Software <http://www.lcsql.com>
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On Mon, Oct 27, 2014 at 12:58 PM, FlexibleLearning.com <
admin at flexiblelearning.com> wrote:

> As Jacque has pointed out, 'empty' and 'zero' depend on context. When doing
> math calculations, I always force a math evaluation...
>
> If t1 + 0  = 0 then ...
>
> If t1 is empty it will then always evaluate to zero.
>
> Might help in your situation.
>
> Best regards,
>
> Hugh Senior
> FLCo
>
>
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