[dba-SQLServer] Warning, the table

When I try to add a field to the table it gives me a "Warning, the table was
created with Ansi Nulls OFF.  The table will be recreated with Ansi Nulls
ON".  I know from experience that this causes the db to go off for days at a
time rebuilding the table.  

What the <expletive deleted> are ansi nulls and why was the table created
with it off?
Why do I need them now?
Is there any way to prevent this and yet still be able to add a field?  
Is there any way to allow setting ansi nulls on but not "rebuilding the
table"?

I already added a field (an int identity) and it told me it was rebuilding
the table for that field.  Why is it having to rebuild the table again.
This is getting rather silly especially since it takes literally days to
rebuild the table.  

John W. Colby
www.ColbyConsulting.com 

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