The iSeries system is an object-based system. All database objects in DB2 UDB for iSeries (tables and indexes for example) are objects in i5/OS. The single-level storage manager manages all storage of objects of the database, so database specific storage structures (for example, table spaces) are unnecessary.
A distributed table allows data to be spread across different database partitions. The partitions included are determined by the nodegroup specified when the table is created or altered. A nodegroup is a group of one or more iSeries systems. A partitioning map is associated with each nodegroup. The partitioning map is used by the database manager to determine which system from the nodegroup will store a given row of data. For more information about nodegroups and data partitioning see the DB2® Multisystem book.
A table can also include columns that register links to data that are stored in external files. The mechanism for this is the DataLink data type. A DataLink value which is recorded in a regular table points to a file that is stored in an external file server.
The DB2 File Manager on a file server works in conjunction with DB2 to provide the following optional functionality:
The DataLinker comprises the following facilities: