Re: Concat field result in select query

Nacef LABIDI a écrit :
> Hi all,
>
> I was wondering if there is a way to concatenate the results of a field
> in a select to return it as a single string.
>
> Example :
>
> my_field
> --------------
> 1
> 2
> 3
>
> select concat_something(my_field) from my_table group by something;
> the result expected would be someting like that : 1/2/3 (with a
> separator it would be really nice)
>
> I hope that I am not asking for too much ;)
>

Something like:

SELECT array_to_string(array(select myfield from mytable), ','));

For example:

sherkin=# select * from t1;
c1 | c2
----+----
1 |
2 | 3
2 | 4
2 | 5
(4 lignes)

sherkin=# SELECT array_to_string(array(select c1 from t1), ',');
array_to_string
-----------------
1,2,2,2
(1 ligne)

--
Guillaume.
http://www.postgresqlfr.org
http://dalibo.com