Re: forming tuple as an attribute inside another tuple in c function

OK but what is the recommended way to get TupleDesc for p_type? I am aware
of RelationNameGetTupleDesc but I shouldn't use it since it is deprecated.
However by using it the code would look something like this (I tested it and
it works as expected):

Datum demo(PG_FUNCTION_ARGS) {

float8 xi = 1;

float8 yi = 2;

float8 xe = 3;

float8 ye = 4;

int32 id = 1;

bool isnull;

TupleDesc tupdesc;
TupleDesc tupdesc_p;

Datum values[3];
Datum vi[2];
Datum ve[2];

HeapTuple tuple;
HeapTuple i;
HeapTuple e;

tupdesc_p = *RelationNameGetTupleDesc*("p_type");

vi[0] = Float8GetDatum(xi);
vi[1] = Float8GetDatum(yi);
i = heap_form_tuple(tupdesc_p, vi, &isnull);

ve[0] = Float8GetDatum(xe);
ve[1] = Float8GetDatum(ye);
e = heap_form_tuple(tupdesc_p, ve, &isnull);

if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
{

ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("function returning record called in context that cannot accept type
record")));

}

BlessTupleDesc(tupdesc);

* * values[0] = HeapTupleGetDatum(i);

values[1] = HeapTupleGetDatum(e);

values[2] = Int32GetDatum(id);

tuple = heap_form_tuple(tupdesc, values, &isnull);

PG_RETURN_DATUM(HeapTupleGetDatum(tuple));
}

On Mon, Sep 27, 2010 at 3:32 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> You've omitted to tell us just
> what's going wrong for you.
>
> regards, tom lane
>