I needed to do this just the other day, here's what I did:
create or replace function explode(_a anyarray) returns setof
anyelement as $$
begin
for i in array_lower(_a,1) .. array_upper(_a,1) loop
return next _a[i];
end loop;
return;
end;
$$ language plpgsql strict immutable;
select * from explode((select col from table where id = whatever)) as
Exploded;
On 29/05/2009, at 6:52 PM, arta...@comcast.net wrote:
----- Original Message -----
From: "Postgres User" <postgres.develo...@gmail.com>
To: "pgsql-general" <pgsql-general@postgresql.org>
Sent: Friday, May 29, 2009 12:21:11 AM GMT -08:00 Tijuana / Baja
California
Subject: [GENERAL] Converting each item in array to a query result row
Hi,
I'd writing a query against a function (pg_proc) that contains 2
fields of an array type. Ideally, I'd like to select 1 row from the
table, but return a query row for each item in the array.
For example, if one row contains the array {"a", "b", "c"}
I'd like the query to return 3 rows, one for each of these elements.
Any idea if this is possible?
Not sure exactly what you want, but this should get you in the ball
park
SELECT f.my_field[i] AS value,
(array['I am one','I am two','I am three'])[i] AS description
FROM my_func(foo) f
JOIN generate_series(1,3) i ON 1=1
Postgres 8.4 will has an unpack() function to convert an array to a
set. Pavel has a write up about doing this in 8.3 and lower here:
http://www.postgres.cz/index.php/PostgreSQL_SQL_Tricks#Array_to_table
I've got some examples of pulling data ouf of arrays here:
http://scottrbailey.wordpress.com/2009/05/20/etl-with-postgres-arrays/
