Beefy Boxes and Bandwidth Generously Provided by pair Networks
good chemistry is complicated,
and a little bit messy -LW
 
PerlMonks  

Re^3: "undef" is not NULL and what to do about it

by runrig (Abbot)
on Feb 21, 2013 at 00:06 UTC ( #1019867=note: print w/replies, xml ) Need Help??


in reply to Re^2: "undef" is not NULL and what to do about it
in thread "undef" is not NULL and what to do about it

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.

.

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1019867]
help
Chatterbox?
[davido]: The code seems pretty sane, and relatively foolproof. I guess I can answer my own question; move() should work across filesystems so long as they're mounted, rw, and not filled up.

How do I use this? | Other CB clients
Other Users?
Others chilling in the Monastery: (2)
As of 2016-12-10 03:05 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    On a regular basis, I'm most likely to spy upon:













    Results (159 votes). Check out past polls.