Re: [SQL] PgSQL 6.5.1 and Group BY pb

Herouth Maoz wrote:
> 
> At 14:08 +0300 on 25/08/1999, Giampiero Raschetti wrote:
> 
> > ...............................
> 
> I think you have a misunderstanding about the purpose of group by statements.
> 
> In fact, the above seems to indicate that you are not well aware of what
> joins are, or at least you don't know that you have to restrict them to
> make sense of your data. You really have to add WHERE g.id = u.id.
>

OK. That's true. I'm not well aware of SQL in general but if you
try out that secuence into postgres 6.4.2 you will see that it works.
So I understand that probably it was not standard. Well.

Let's take a look at this same problem without any join involved
and if possible let me know how to obtain my target:

xaxa=> \d comuni
Table    = comuni
+----------------------------------+----------------------------------+-------+
|              Field               |              Type                |
Length|
+----------------------------------+----------------------------------+-------+
| produtt                          | varchar()                       
|    40 |
| unital                           | varchar()                       
|    40 |
| comune                           | varchar()                       
|    40 |
| login                            | varchar()                       
|     8 |
+----------------------------------+----------------------------------+-------+

xaxa=> select * from comuni;               
produtt|         unital|comune      |login
-------+---------------+------------+-----
xxx    |199900200000100|POGGIRIDENTI|user1
yyy    |199900200000100|POGGIRIDENTI|user2
yyy    |199900200000100|ARDENNO     |USER3
yyy    |199900200000100|BORMIO      |user2
(4 rows)

xaxa=> select * from comuni group by login;
ERROR:  Illegal use of aggregates or non-group column in target list
xaxa=> 

This works too on Postgres 6.4.2 so how can I obtain a list of
unique users from this table on 6.5.1 ?

Many Thanks

-- 
Best Regards
----------------------------
Giampiero Raschetti
Sistemi Innovativi
Banca Popolare di Sondrio
----------------------------