Latency is a cloud killer :-)
This is not to say it can/should not be done, but typically you'll want to
give some thought to app design to accommodate it.
eg if you're going query a table "n" times over the course of a certain
time duration, perhaps drag the table (or subset) down to the local node
once into a local table or mview, and then use it.
One risk of cross-database joins is the optimizer making the decision on
where to do the join - driving_site can mitigate this risk to some degree.
On Thu, Jul 15, 2021 at 10:46 PM Jeff Chirco <backseatdba@xxxxxxxxx> wrote:
What is your opinion on joining to a table over a database link that
resides in the cloud and your local database is on prem? And what if this
cloud instance is MSSQL and your local is Oracle?
We have something in the works that I just found out is supposed to go to
production next week. They are joining local and remote tables together. So
far in testing things are looking ok but the amount of data is limited
right now, I am unsure how much it will grow to.
Wondering if anyone has any experience with this.
Thanks,
Jeff
