[GENERAL] number of records returned by cursors

[Zac]

Hi,
does anyone know if there is a way (in plpgsql) to obtain the number of 
records returned by a cursor without fetching them all?

Using "FOUND" and "GET DIAGNOSTICS row_count" variables doesn't help me: 
the only way seems to be fetching all the records.

I try to explain it better:

CREATE OR REPLACE FUNCTION test_cur() RETURNS void AS
$$
DECLARE
        c CURSOR FOR SELECT 'foo' UNION SELECT 'bar';
        i integer;
        t text;
BEGIN
        OPEN c;
        RAISE INFO 'FOUND: %', FOUND;
        GET DIAGNOSTICS i = row_count;
        RAISE INFO 'row_count: %', i;

        FETCH c INTO t;
        RAISE INFO '1 row (of 2) fetched: %', t;
        RAISE INFO 'FOUND: %', FOUND;
        GET DIAGNOSTICS i = row_count;
        RAISE INFO 'row_count: %', i;

        FETCH c INTO t;
        RAISE INFO '2 row (of 2) fetched: %', t;
        RAISE INFO 'FOUND: %', FOUND;
        GET DIAGNOSTICS i = row_count;
        RAISE INFO 'row_count: %', i;

        CLOSE c;
END;
$$ LANGUAGE plpgsql;

SELECT test_cur();
INFO:  FOUND: f
INFO:  row_count: 0
INFO:  1 row (of 2) fetched: bar
INFO:  FOUND: t
INFO:  row_count: 0
INFO:  2 row (of 2) fetched: foo
INFO:  FOUND: t
INFO:  row_count: 0
 test_cur
----------

(1 row)


Thank you.
Zac

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