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Thread: Update Join Query

Update Join Query

From
"Daniel Futerman"
Date:
Hi,

Looking for the correct syntax for an UPDATE LEFT JOIN query in PostgreSQL.

The equivalent MySQL query is :

    UPDATE
        Foo f LEFT JOIN Goo g on f.Foo_ID = g.Goo_ID
    SET
        f.Foo_ID = g.Goo_ID
    WHERE
        f.Foo_ID IS NOT NULL;


 When I try to run this in Postgres, i get the following error:

ERROR:  syntax error at or near "LEFT"

Is it possible to have UPDATE JOIN queries in PostgreSQL?

Thanks.

Re: Update Join Query

From
Mark Roberts
Date:
update foo
set foo_id = g.goo_id
from goo g
where foo.foo_id = g.goo_id and foo.foo_id is not null

I think. :)

-Mark

On Mon, 2008-06-23 at 21:43 +0200, Daniel Futerman wrote:
> Hi,
>
> Looking for the correct syntax for an UPDATE LEFT JOIN query in
> PostgreSQL.
>
> The equivalent MySQL query is :
>
>     UPDATE
>         Foo f LEFT JOIN Goo g on f.Foo_ID = g.Goo_ID
>     SET
>         f.Foo_ID = g.Goo_ID
>     WHERE
>         f.Foo_ID IS NOT NULL;
>
>
>  When I try to run this in Postgres, i get the following error:
>
> ERROR:  syntax error at or near "LEFT"
>
> Is it possible to have UPDATE JOIN queries in PostgreSQL?
>
> Thanks.

Re: Update Join Query

From
Antonio Perez
Date:


--- El lun 23-jun-08, Daniel Futerman <daniel.futerman@gmail.com> escribió:
De: Daniel Futerman <daniel.futerman@gmail.com>
Asunto: [GENERAL] Update Join Query
A: pgsql-general@postgresql.org
Fecha: lunes, 23 junio, 2008, 4:43 pm

Hi,

Looking for the correct syntax for an UPDATE LEFT JOIN query in PostgreSQL.

The equivalent MySQL query is :

    UPDATE
        Foo f LEFT JOIN Goo g on f.Foo_ID = g.Goo_ID
    SET
        f.Foo_ID = g.Goo_ID
    WHERE
        f.Foo_ID IS NOT NULL;


 When I try to run this in Postgres, i get the following error:

ERROR:  syntax error at or near "LEFT"

Is it possible to have UPDATE JOIN queries in PostgreSQL?

Thanks.


Try this..

UPDATE Foo f
    SET f.Foo_ID = g.Goo_ID
FROM (
    select g.Goo_ID from Goo g
    RIGHT JOIN Foo f on (f.Foo_ID = g.Goo_ID)
    WHERE f.Foo_ID IS NOT NULL;
    ) g
   

Re: Update Join Query

From
Antonio Perez
Date:


--- El lun 23-jun-08, Daniel Futerman <daniel.futerman@gmail.com> escribió:
De: Daniel Futerman <daniel.futerman@gmail.com>
Asunto: [GENERAL] Update Join Query
A: pgsql-general@postgresql.org
Fecha: lunes, 23 junio, 2008, 4:43 pm

Hi,

Looking for the correct syntax for an UPDATE LEFT JOIN query in PostgreSQL.

The equivalent MySQL query is :

    UPDATE
        Foo f LEFT JOIN Goo g on f.Foo_ID = g.Goo_ID
    SET
        f.Foo_ID = g.Goo_ID
    WHERE
        f.Foo_ID IS NOT NULL;


 When I try to run this in Postgres, i get the following error:

ERROR:  syntax error at or near "LEFT"

Is it possible to have UPDATE JOIN queries in PostgreSQL?

Thanks.

sorry the last message have a error

try whit this

update foo set Foo_ID = goo.Goo_ID from goo where goo.Goo_id = foo.Foo_id and foo_ID IS NOT NULL;

Re: Update Join Query

From
Craig Ringer
Date:
Daniel Futerman wrote:

> Is it possible to have UPDATE JOIN queries in PostgreSQL?

Yes:

UPDATE target
     ....
FROM othertable;

As far as I know Pg can only do an inner join on the update target. This
can be easily be turned into an outer join with something like:

UPDATE target
    ....
FROM target t LEFT OUTER JOIN othertable
WHERE target.id = t.id;

or similar. I haven't checked to see whether this results in an extra
scan in the query plan; you might want to use EXPLAIN ANALYZE to examine
how Pg will execute the query.

--
Craig Ringer