Re: [HACKERS] empty concatenate

>
> Hi,
>
> I try concatenate text via standard '||' oprerator, but result is
> interesting:
>
> PgSQL 6.5.3/7.0:
> ~~~~~~~~~~~~~~~
> test=> select * from x;
> a |b
> ---+---
> AAA|BBB
> xxx|
> (2 rows)
>
> test=> select a || b from x;
> ?column?
> --------
> AAABBB
> <-------------- empty !
> (2 rows)

NULL's can not be concatenated, but '' can. Looks fine to me:

---------------------------------------------------------------------------

test=> create table ff (x text, y text);
insCREATE
test=> insert into ff values ('a','');
INSERT 19082 1
test=> insert into ff values ('b',null);
INSERT 19083 1
test=> select x || y from ff;
?column?
----------
a

(2 rows)

--
Bruce Momjian | http://www.op.net/~candle
maillist(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
+ Christ can be your backup. | Drexel Hill, Pennsylvania 19026