which is the best

[slackman(at)unika(dot)ac(dot)id]

hii all,
Now I have 3 database A,B,C is working in Interbase v 5.6,
but Interbas v 5.6 is no longger can hold what the client wants,
I will conver it in Postgresql, I need your advice which is the
bertter result: 

(1):
unika (schema)
   |
   |------ A
   |------------ B
   |------------------- C

(2) create database A, create database B, create database C 

thank you all