Thread: Concatenating does not work properly

Concatenating does not work properly

From
Michal Taborsky
Date:
Hello,

I am facing a problem I cannot really explain to myself. I have a table 
with personal data which has columns surname, firstname, secondname, 
title and I want to do a simple select like this:

SELECT (surname || ', ' || firstname || ' ' || secondname) as fullname 
FROM person

For some rows (from what I recognised it is with rows, which have the 
title column empty) it works, for some it returns empty string:

akcent=# SELECT (surname || ', ' || firstname || ' ' || secondname) as 
fullname, title_pre, surname, firstname, secondname FROM person;
       fullname        | title_pre | surname  | firstname | secondname
-----------------------+-----------+----------+-----------+------------                       | Ing.      | Taborsky |
Michal   |                       | Ing.      | Barta    | David     | Novak, Josef          |           | Novak    |
Josef    | Saroch, Adrian Walter |           | Saroch   | Adrian    | Walter
 
(4 rows)

Is that a bug or am I missing something ?

Thanks,
Michal



Re: Concatenating does not work properly

From
Lee Harr
Date:
In article <b719sp$24ki$1@news.hub.org>, Michal Taborsky wrote:
> Hello,
> 
> I am facing a problem I cannot really explain to myself. I have a table 
> with personal data which has columns surname, firstname, secondname, 
> title and I want to do a simple select like this:
> 
> SELECT (surname || ', ' || firstname || ' ' || secondname) as fullname 
> FROM person
> 
> For some rows (from what I recognised it is with rows, which have the 
> title column empty) it works, for some it returns empty string:
> 
> akcent=# SELECT (surname || ', ' || firstname || ' ' || secondname) as 
> fullname, title_pre, surname, firstname, secondname FROM person;
> 
>         fullname        | title_pre | surname  | firstname | secondname
> -----------------------+-----------+----------+-----------+------------
>                         | Ing.      | Taborsky | Michal    |
>                         | Ing.      | Barta    | David     |
>   Novak, Josef          |           | Novak    | Josef     |
>   Saroch, Adrian Walter |           | Saroch   | Adrian    | Walter
> (4 rows)
> 
> Is that a bug or am I missing something ?
> 


I bet that one of surname, firstname, or secondname is NULL
in those rows where fullname is blank.


You might try:

SELECT (coalesce(surname, '') || ', ' ||        coalesce(firstname, '') || ' ' ||       coalesce(secondname, '')) as
fullnameFROM person;