what is the impact of Database size on Performemce

I need some information to understand what is the impact of Database size on
the performemce.


Few questions :

1. Is there any impact?
2. Does one very large table impact the performence of the the whole DB,
meaning the overall performence and access the other tables.
3. What are the ways to reduce the impact of the DB size  on the DB
performence


I will apreciate help in regards .


Thanks Avner