Strange interaction of union and expressions

On Apr 20, 2005, at 1:24 PM, Aaron Bingham wrote:

create table a (foo varchar);
insert into a (foo) values ('baz');
create table b (foo varchar);
insert into b (foo) values ('woof');
select '"' || foo || '"' as foo
from (select foo from a) as bar
union select foo from b;

No, it's doing what you asked.

You mean:

select '"' || foo || '"' from (select foo from a union select foo from
b) as subq;

Right?

-Kevin

Kevin Murphy <murphy2@speakeasy.net> writes:

On Apr 20, 2005, at 1:24 PM, Aaron Bingham wrote:

create table a (foo varchar);
insert into a (foo) values ('baz');
create table b (foo varchar);
insert into b (foo) values ('woof');
select '"' || foo || '"' as foo
from (select foo from a) as bar
union select foo from b;

No, it's doing what you asked.

You mean:

select '"' || foo || '"' from (select foo from a union select foo from
b) as subq;

Right?

Ah, I get it now. Thanks!

--
--------------------------------------------------------------------
Aaron Bingham
Software Engineer
Cenix BioScience GmbH
--------------------------------------------------------------------

I see no problem. You get what you want.

Correct query is:

select '"' || foo || '"' as foo
from (select foo from a union select foo from b ) as bar;

Oleg

On Wed, 20 Apr 2005, Aaron Bingham wrote:

Hello all,

We noticed some very odd behavior today with Postgres 7.4.5

Running the following SQL:

create table a (foo varchar);
insert into a (foo) values ('baz');
create table b (foo varchar);
insert into b (foo) values ('woof');
select '"' || foo || '"' as foo
from (select foo from a) as bar
union select foo from b;

Produces this output:

foo
-------
"baz"
woof
(2 rows)

I would expect the following instead:

foo
-------
"baz"
"woof"
(2 rows)

Is this a known issue? Has it been fixed?

Thanks,

Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83

On Wed, Apr 20, 2005 at 07:24:08PM +0200, Aaron Bingham wrote:

Hi,

create table a (foo varchar);
x insert into a (foo) values ('baz');
create table b (foo varchar);
insert into b (foo) values ('woof');
select '"' || foo || '"' as foo
from (select foo from a) as bar
union select foo from b;

It's a precedence issue; not a problem really. Try this:

select '"' || foo || '"' as foo
from (select foo from a
union select foo from b) as bar;

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"�Que diferencia tiene para los muertos, los hu�rfanos, y aquellos que han
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