Re: [HACKERS] generated columns

On Thu, Nov 22, 2018 at 10:16 AM Peter Eisentraut
<peter(dot)eisentraut(at)2ndquadrant(dot)com> wrote:
> On 15/11/2018 15:10, Robert Haas wrote:
> > I don't have a strong position on 1 vs. 2 vs. 3, but I do think it
> > would be nicer not to use '\0' as a column value. I'd suggest you use
> > 'n' or '0' or '-' or some other printable character instead.
>
> I had carefully considered this when attidentity was added. Using '\0'
> allows you to use this column as a boolean in C code, which is often
> convenient. Also, there are numerous places where a pg_attribute form
> or a tuple descriptor is initialized to all zeroes, which works well for
> most fields, and adding one exception like this would create a lot of
> extra work and bloat the patch and create potential for future
> instability. Also note that a C char '\0' is represented as '' (empty
> string) in SQL, so this also creates a natural representation in SQL.

I'm not really convinced. I think that the stdbool work you've been
doing shows that blurring the line between char and bool is a bad
idea. And I believe that on general principle, anyway.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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