IBM Understanding Data Server Client License and DB2 Data Partitioning Features

A partitioned database is a database created across multiple database partitions. Each database partition has its own processes, memory, and data storage. These resources are not shared between partitions. Queries submitted to the DB2 database are distributed to each database partition and processed in parallel. If there are multiple processors in each database partition node, internal parallelism can be used to achieve better performance. There could be more than one database partition created on a machine. And this is transparent to the user, who does not have to know what happens behind the scenes.

In this section, we discuss the considerations pertinent for a partitioned database system.

Licensing for a partitioned database

The DB2 Data Partitioning Feature (DPF) requires a separate additional license from that of the Enterprise Server Edition (ESE) license. In DB2 9.5, it is only available through InfoSphere package (see 1.2.4, “Other DB2 products” on page 8). The DPF license has to be applied to all the participating database machines. The DB2 Data Partitioning feature can be activated using the db2licm command.

For licensing in detail, see 1.3.4, “License considerations” on page 20.

For a partitioned database system on Linux and UNIX, where more than one machine participates, a shared directory has to be created on a file system and used as the instance home path. The DB2 instance is created in this shared home directory, and the instance configuration files will be accessible by all database partitions.

NFS

The Network File System (NFS) is a widely used protocol for remote file access, and it is built based on a Remote Procedure Call (RPC). The NFS allows users and applications to access files over the network as if the remote files are on the local disks.

In a partitioned database environment, one computer is set up as the NFS server. The instance home directory is created on this server and exported to other participating machines, which are configured as the NFS clients. The file systems exported on the NFS server are mounted by the NFS clients. The DB2 instance configuration files located on this directory could be accessed by every partition.

40DB2 Deployment Guide