MS Access can connect (link) to 2 databases or more in a time ... can Postgres do the same thing?
I would like to link from within one database to another, so that I can share a table across two databases ?
No. However, the contrib/dblink program in the contributed software section of the source distribution will let you do this.
In 7.3, Postgres will have full schema support, so this will mostly become a non-issue.
Chris