Strange interaction of union and expressions

[Aaron Bingham <bingham@xxxxxxxxxxxxxxxxxxxx>]

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,

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


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