How to send multiple parameters to a pl/pgsql function
I need to create a pl/pgsql function witch accept a list of parameters and evaluate them.
I've tried this
CREATE OR REPLACE FUNCTION get_first_valid (lista_elementi VARCHAR[])
RETURNS VARCHAR AS $$
DECLARE
the_one VARCHAR;
BEGIN
IF (ARRAY_UPPER(lista_elementi, 1) IS NOT NULL) THEN
FOR i IN 1..ARRAY_UPPER(lista_elementi, 1) LOOP
the_one := lista_elementi[i];
IF ((the_one IS NOT NULL) AND (TRIM(the_one) != '') ) THEN
EXIT;
END IF;
END LOOP;
ELSE
the_one := NULL;
END IF;
RETURN (the_one);
END;
$$ LANGUAGE 'plpgsql' VOLATILE;
I know that postgresql array implementation is not right complete and that if just
one element of array is NULL the basics array function (array_dims, array_upper, etc.) returns NULL.
I need to send a list of parameters (which could contain NULL values) and evaluate the parameters excluding NULL values
is this possible?
any suggestion?
Sgarbossa Domenico
Extacy Project Leader
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I know that postgresql array implementation is not right complete and that if just
one element of array is NULL the basics array function (array_dims, array_upper, etc.) returns NULL.
I need to send a list of parameters (which could contain NULL values) and evaluate the parameters excluding NULL values
is this possible?
any suggestion?
It's not true. Dimensions are stored independent to content.
postgres=# create or replace function foo(int[])
returns int as $$
declare s int = 0; i integer;
begin
for i in select generate_subscripts($1,1)
loop
s := s + coalesce($1[i],0);
end loop;
return s;
end;
$$ language plpgsql;
CREATE FUNCTION
postgres=# select foo(array[1,2]);
foo
─────
3
(1 row)
postgres=# select foo(array[1,2, null, 3]);
foo
─────
6
(1 row)
Pavel Stehule <pavel.stehule@gmail.com> writes:
I know that postgresql array implementation is not right complete and that if just
one element of array is NULL the basics array function (array_dims, array_upper, etc.) returns NULL.
It's not true. Dimensions are stored independent to content.
I wonder if the OP is using an old version of Postgres. Since 8.2 we
can handle null elements of arrays, but 8.1 and older couldn't --- the
whole array went to null if you tried to include a null in it.
regards, tom lane