I presume that you are aware of what db links are and I suggest that you create db links. Here are few more tips:
Depending on when you will be accessing these tables, you may choose to go for either a normal view or a materialized view.
You do not need to 'refresh' a regular view, you can directly go ahead and run the view whenever needed, but that may be a hit on the performance.
With a Materialized view, you will not be making remote database calls when you access this query-assuming that you create & access this Materialized view in one database. But you may then need to refresh this view in a timely fashion-the frequency depends on your application needs(hourly/daily/weekly etc).
The up side of materialized view is that you can have the query results faster.
Hope I have provided enough information for you to decide.
You may opt for DB link
select * from <schema_name>.emp@DB_LINK1
select * from <schema_name>.emp@DB_LINK2
select * from <schema_name>.emp@DB_LINK3
select * from <schema_name>.emp@DB_LINK4
select * from <schema_name>.emp@DB_LINK5
>>CAN YOU PLEASE SUGGEST WHICH WILL BE THE BEST WAY TO ACHIVE THIS. Materilized View or normal VIEW or is there any other metod to achive this.
As far as there is not much of updates /inserts performed on the tables I would suggest you to go with Mview for faster results.