Naming of Schema Objects Using Database Links
Oracle uses the global database name to name the schema objects globally using the following scheme:

schema.schema_object@global_database_name


where:

schema

is a collection of logical structures of data, or schema objects. A schema is owned by a database user and has the same name as that user. Each user owns a single schema.

schema_object

is a logical data structure like a table, index, view, synonym, procedure, package, or a database link.

global_database_name

is the name that uniquely identifies a remote database. This name must be the same as the concatenation of the remote database's initialization parameters DB_NAME and DB_DOMAIN, unless the parameter GLOBAL_NAMES is set to FALSE, in which case any name is acceptable.




For example, using a database link to database SALES.DIVISION3.ACME.COM, a user or application can reference remote data as follows:

SELECT * FROM scott.emp@sales.division3.acme.com; # emp table in scott's schema
SELECT loc FROM scott.dept@sales.division3.acme.com;