Archives of the TeradataForum
Message Posted: Thu, 18 Feb 2010 @ 10:33:06 GMT
Subj: | | Re: Linking to and Querying Access database |
|
From: | | Stover, Terrance |
Paul GRAHAM wrote:
| I'm attempting to link to an Access database to allow us to query against data held in the Teradata environment. I have been able to
connect to the required Access database using the Microsoft Access Driver, but if I want to see the Teradata databases I have to disconnect from
the Machine Data Source then reconnect to be able to view our Teradata databases. Is there any way I can have both open to allow querying across
the 2 databases. | |
That's an exceptionally bad idea. Access will one one query against Teradata for each row in the local table. You can easily throw millions
of queries at the server. The best approach is to create a table on Teradata and upload the results from access, you will get one insert
statement per access row. If the data isn't too big you can download the data to access.
Write a passthrough query that filters the appropriate rows, then use the passthrough query as the data source for a create table query in
access.
Quick way to download data. Probably need to set the timeout to something greater than the default value of 60 seconds. You can dynamically
create the sql for the passthrough query in vba.
|