Re: Accessing 2 different databases in the same query ?

On Monday 02 June 2003 10:39, Nagib Abi Fadel wrote:
> From what i read dblink let's us access another database in the same query
> ... Which is great. But does it slow down the query ??

What do You mean slow down ? In compare to what ?
If You question was is such query slower than the query on tables in local
database, the answer is YES. Let me describe the mechanism of dblink:
Your backend process becomes client of another backend (on same or different
server). dblink establishes connection to remote database, executes the
query, and send data to Your backend.

I use dblink over slow ISDN connection, so You can figure out how slow it can
be, but that is the beauty of dblink: You can query servers that are anywhere
on the network !

> And what about making references between tables (creating foreign keys) is
> it possible ?????
>

No, but you can create "remote view" using dblink and then do the same thing
using triggers(foreign keys are just specific triggers).
There are few samples in dblink documentation - check them out !

Regards !

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