Thread: Assigning values to array components.

Assigning values to array components.

From
Rich Cullingford
Date:
Hello All,
I have a small application (based on sorting inet[] arrays) that 
requires building an array of bigints, one for each inet in the array. 
This is doable in most programming languages with a notation like:
     inet_bigints[i] := inet2bigint(ip)

Unfortunately, plpgsql doesn't seem to allow that kind of assignment, as 
loading the following into psql reveals:

create or replace function foobaz()
RETURNS bigint[]
AS '
DECLARE    answer bigint[];
BEGIN  answer[1] := 12345;  RETURN answer;
END;
'
LANGUAGE 'plpgsql';

When I try to run this:

select foobaz();
WARNING:  plpgsql: ERROR during compile of foobaz near line 4
ERROR:  parse error at or near "["

The system also won't let me initialize the array in the DECLARE 
section. I've looked through the archives for the past few years for 
hints about this, but haven't found anything. Is there a plpgsql 
reference that's more 'complete' than the one that comes with the PG 
distribution?

Any help greatly appreciated.                               Rich Cullingford
rculling@sysd.com



Re: Assigning values to array components.

From
Tom Lane
Date:
Rich Cullingford <rculling@sysd.com> writes:
> create or replace function foobaz()
> RETURNS bigint[]
> AS '
> DECLARE
>      answer bigint[];
> BEGIN
>    answer[1] := 12345;
>    RETURN answer;
> END;
> '
> LANGUAGE 'plpgsql';

> select foobaz();
> WARNING:  plpgsql: ERROR during compile of foobaz near line 4
> ERROR:  parse error at or near "["

IIRC, Joe Conway fixed that for 7.4.  I can get your example to work
in CVS tip if I modify the DECLARE to
answer bigint[] = ''{}'';

Without that, you're trying to combine a NULL array with a nonnull
entry, which is going to give a NULL result.
        regards, tom lane