[DB-SIG] connect to multiple databases at the same time

[M.-A. Lemburg]

zongzhi liu wrote:
> I am using sqlite3 a lot.  As a database growing larger and larger, I would
> like to seperate some tables into another database.  In sqlite3, you can use
> something like:
> select * from db_a.table1 join db_b.table1 using (ID)
> 
> However, I cannot figure out how to use such statement in python.  You help
> will be greatly appreciated.

That would be a cross-database join. A few databases are able to
handle such joins, e.g. DB2. You have to define access to the
second DB in the first DB and then have the database engine
apply the join for you.

In Python, you'd simply run the query and get back the results.

There are also meta-drivers which provide a similar logic without
the need to modify the databases, e.g.

http://www.easysoft.com/products/data_access/odbc_odbc_join_engine/index.html?location=Easysoft%20Data%20Access%20body

You can use our mxODBC to access this driver from Python.

-- 
Marc-Andre Lemburg
eGenix.com

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