[storm] How to CREATE DATABASE using Storm

[Mario Zito]

Jamu,
Thanks for the quick response !
I will try this and then report results back.
Thanks,
Mario

2010/4/22 Jamu Kakar <jkakar at kakar.ca>

> Hi Mario,
>
> On Thu, Apr 22, 2010 at 12:37 AM, Mario Zito <mazito at analyte.com> wrote:
> > I'd like to  to connect to a db server, create a
> > database, and then start using it. However, it appears that the
> > Storm api assumes the existence of a database to connect to, before you
> > can execute some sql. I'm not able to connect to the server without a
> > database specified.
> >
> > So, I tried:
> >
> >     db= create_database("postgres://postgres:password@localhost
> /postgres")
> >     cx= db.connect()
> >     cx.execute("CREATE DATABASE demo_1")
> > But I get:
> >
> >   psycopg2.InternalError: CREATE DATABASE cannot run inside a transaction
> > block
> >
> > I tried some alternatives, like using raw_execute(), but have no
> success. Is
> > there a solution to this using Storm ?
> > I know I can resolve this starting a child process and executing pgsql
> with
> > a sql script, but would like a better solution :-)
>
> I don't know of a way to do this with Storm.  Storm issues BEGIN
> statements transparently, so any query you try to run will result in
> a transaction being created.  You can probably work around the
> problem with something like the following (untested) code:
>
> database = create_database("postgres://localhost/postgres")
> connection = database.raw_connect()
>
> At this point 'connection' is a connection object retrieved from
> psycopg2 (ie: not a storm.database.Connection instance).  You should
> be able to use this raw connection to do what you want:
>
> cursor = connection.cursor()
> cursor.execute("CREATE DATABASE demo_1")
> cursor.close()
> connection.commit()
> connection.close()
>
> This is a basically hack, though.  You'd only be using Storm to
> establish a connection with the database in this case... it may
> easier to use the DB-API [1] directly to create your database and
> then switch over to using Storm to work with it.
>
> Thanks,
> J.
>
> [1] http://www.python.org/dev/peps/pep-0249/
>



-- 
Mario A. Zito
ANALYTE SRL
Parana 457, piso 2, of. 'A'
(C1033AAI) Buenos Aires, Argentina
tel: (54-11) 5258-0205 int 138
mazito at analyte.com
www.analyte.com
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