Re: Understanding Datum

If Datum contains only the value (not having type specific info.), then
Suppose i want to print the Datum V value (already defined in postgres)
then printf("%??", V);

Because V is assigned by PG_GETARG_POINTER(1);
I don't having the information of type Datum.

How to print the value of Datum in postgres?

On Thu, Mar 24, 2011 at 2:35 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> Nick Raj <nickrajjain(at)gmail(dot)com> writes:
> > In postgres, typedef uintptr_t Datum
> > Datum is getting value from PG_GETARG_POINTER(1);
> > But, now problem is how would i know the type of PG_GETARG_POINTER(1)
> > (postgres internally pass this argument) to figure out datum type?
>
> Datum does not carry any type information, only a value. Functions are
> typically coded to know their input types a priori. If you want to
> write code that is not type-specific then you'd better be passing around
> type OIDs as well as values.
>
> regards, tom lane
>
> --
> Sent via pgsql-general mailing list (pgsql-general(at)postgresql(dot)org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-general
>