>
> > Once atttypmod is exposed to applications it will be much harder to
> > change its representation or meaning
>
> Yeah, that is what I'm worried about too...
>
> - Tom (the other "tgl")
Well, atttypmod is stored in various C structures, like Resdom, so we
would need some C representation for the type, even it is just a void *.
Very few system columns are varlena/text, and for good reason, perhaps.
Such a change is certainly going to make things in the backend slightly
harder, so please let me what advantage a varlena atttypmod is going to
have.
Zero overhead for types that don't use it is meaningless, because the
varlena length is 4 bytes, while current atttypmod is only two. Second,
I don't see how a varlena makes atttypmod less type-specific. We
currently return a -1 when it is not being used.
--
Bruce Momjian | 830 Blythe Avenue
maillist@candle.pha.pa.us | Drexel Hill, Pennsylvania 19026
+ If your life is a hard drive, | (610) 353-9879(w)
+ Christ can be your backup. | (610) 853-3000(h)
