Re: returning composite types.

Franco Bruno Borghesi wrote:
> yes, i was trying to do something like that, but it breaks always in the same 
> place, first I thought that it was because of the way I was assigning values 
> to the fields of my row, but now I'm beginning to think that the reason is 
> the way I pass the row to f2. 
> 
> Here is the error:
> franco=# SELECT f1();
> WARNING:  Error occurred while executing PL/pgSQL function f1
> WARNING:  line 5 at select into variables
> ERROR:  Attribute "result" not found
> 
> CREATE TYPE mytype AS (val1 INTEGER, val2 INTEGER, val3 INTEGER);
> 
> CREATE OR REPLACE FUNCTION f1() RETURNS mytype AS '
> DECLARE   
>    result mytype%ROWTYPE;
> BEGIN
>    result.val1:=1;   
>    SELECT val2, val3 INTO result.val2, result.val3 FROM f2(result);

It looks like plpgsql doesn't support composite type variables as 
arguments to functions that are called from within a function. The error 
is saying it cannot find an attribute named result -- that's because 
there is no *attribute* called result, there is a rowtype variable.

I'm not sure right off what is involved in fixing this, but you can 
always pass the individual attributes to f2:

CREATE TYPE mytype AS (val1 INTEGER, val2 INTEGER, val3 INTEGER);

CREATE OR REPLACE FUNCTION f2(int,int,int) RETURNS mytype AS '
DECLARE   arg1 ALIAS FOR $1;   arg2 ALIAS FOR $2;   arg3 ALIAS FOR $3;   newval2 int;   newval3 int;   result
mytype%ROWTYPE;
BEGIN   newval2 := coalesce(arg2,2) * arg1;   newval3 := coalesce(arg3,3) * arg1;   SELECT INTO result.val1,
result.val2,result.val3     arg1, newval2, newval3;   RETURN result;
 
END;
' LANGUAGE 'plpgsql';

CREATE OR REPLACE FUNCTION f1(int) RETURNS mytype AS '
DECLARE   result mytype%ROWTYPE;
BEGIN   result.val1:=$1;   SELECT INTO result.val2, result.val3 val2, val3     FROM f2(result.val1, result.val2,
result.val3);  RETURN result;
 
END;
' LANGUAGE 'plpgsql';

regression=# select * from f1(2); val1 | val2 | val3
------+------+------    2 |    4 |    6
(1 row)

HTH,

Joe