an empty string IS a NULL. There is no difference at all.

I think the point is you can not select the data using, e.g.WHERE colname = ''.

So how do you represent unknown values? By using a default "UNKNOWN"?

Sometimes you know what the value is, and it's blank. There's just too many ways to look at it.

.

In reply to Re^3: "undef" is not NULL and what to do about it by runrig
in thread "undef" is not NULL and what to do about it by Ovid

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