A distributed database can be implemented under HiRDB by using the remote database access facility of DF/UX (Distributing Facility/for UNIX). The remote database access facility consists of two facilities, the distributed client facility and the distributed server facility.
When HiRDB at the local node is used as a distributed client, it is possible to access a database at a remote distributed server (a UAP of the HiRDB at the local node can access a remote database at another node's DBMS). This capability is implemented using the distributed client facility of DF/UX.
When the UAP is created, you write the HiRDB SQL statements in the same way as for a UAP used for local access to the HiRDB database at the local node. You specify in the SQL statements the distributed server's table name, a name indicating the location of the database, etc. It must be noted that there are restrictions on UAP creation; for details on these restrictions, see the manual HiRDB Version 8 UAP Development Guide.
Figure 27-1 provides an overview of the distributed client facility.
Figure 27-1 Distributed client facility overview
When HiRDB at the local node is used as a distributed server, it is possible for a database at a remote distributed client at a remote node to access this distributed server (the DBMS of a remote node can access the HiRDB database at the local node). This capability is implemented using the distributed server facility of DF/UX. Figure 27-2 provides an overview of the distributed server facility.
Figure 27-2 Distributed server facility overview