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Thread: Using Aliases in Select

Using Aliases in Select

From
Christian Rudow
Date:
I join 2 tables that both have a row "mytext".
I want to use both text fields in the select (projection) clause, giving
alias names to them.

select tab1.name, tab1.mytext text1, tab2.mytext text2
from tab1, tab2
where tab1.tab1_id = tab2.tab1_id

but ...

ERROR:  Column 'mytext' is ambiguous

Is there a solution to this ?

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Christian Rudow                 E-Mail: Christian.Rudow@thinx.ch
ThinX networked business services    Stahlrain 10, CH-5200 Brugg
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Re: [SQL] Using Aliases in Select

From
Andy Lewis
Date:
I'll take a stab at this one:

Try:
select tab1.name, tab1.mytext as text1, tab2.mytext as text2
from tab1, tab2 where tab1.tab1_id = tab2.tab1_id

I believe that this will fix it.

Andy

On Mon, 2 Aug 1999, Christian Rudow wrote:

> I join 2 tables that both have a row "mytext".
> I want to use both text fields in the select (projection) clause, giving
> alias names to them.
> 
> select tab1.name, tab1.mytext text1, tab2.mytext text2
> from tab1, tab2
> where tab1.tab1_id = tab2.tab1_id
> 
> but ...
> 
> ERROR:  Column 'mytext' is ambiguous
> 
> Is there a solution to this ?
> 
> -- 
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Christian Rudow                 E-Mail: Christian.Rudow@thinx.ch
> ThinX networked business services    Stahlrain 10, CH-5200 Brugg
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>

Re: [SQL] Using Aliases in Select

From
Tom Lane
Date:
Christian Rudow <Christian.Rudow@thinx.ch> writes:
> select tab1.name, tab1.mytext text1, tab2.mytext text2
> from tab1, tab2
> where tab1.tab1_id = tab2.tab1_id
> ERROR:  Column 'mytext' is ambiguous

As Oleg points out, you need to write AS text1 and so forth.  The AS
is not optional when labeling output columns, even though you are
allowed to leave it out in the FROM list.  But I am wondering about
the error message --- all the Postgres versions that I have sayERROR:  parser: parse error at or near "text1"
which may not be too helpful but at least it's not outright
misleading.  What version are you using?
        regards, tom lane

Re: [SQL] Using Aliases in Select

From
Christian Rudow
Date:
Andy Lewis wrote:

> select tab1.name, tab1.mytext as text1, tab2.mytext as text2
> from tab1, tab2 where tab1.tab1_id = tab2.tab1_id
> 
> I believe that this will fix it.
> 
> Andy

Yes it does.
My knowledge of SQL all comes from working with Informix databases.
ThanX a lot !

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Christian Rudow                 E-Mail: Christian.Rudow@thinx.ch
ThinX networked business services    Stahlrain 10, CH-5200 Brugg
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~