Chapter 7. Federated Database Access

This chapter discusses:

  • Federated System features, concepts, terminology, and usage.

  • How to plan, configure, and administer a federated system.

  • How to interface with a federated system.

Depending on the data sources that you want to access, you might need to install and configure:

  • DB2 Relational Connect, a separately orderable IBM product that is used with DB2 for UNIX and Windows, Enterprise Server Edition. Relational Connect feature contains wrappers for the non-IBM relational databases.

    • It is required if you want to access data stored in Oracle, Sybase, Microsoft SQL Server, and ODBC data sources.

    • You can access and join data from different data sources with a single SQL statement and a single interface.

    • It provides fast and robust connectivity to IBM mainframe databases for e-business and other applications running under UNIX and Windows operating systems.

  • DB2 Life Sciences Data Connect enables a DB2 federated system to integrate genetic, chemical, biological, and other research data from distributed sources. DB2 Life Sciences Data Connect supports the following data sources:

    • A table-structured file has a regular structure consisting of a series of records, where each record contains the same number of fields, separated by an arbitrary delimiter. A null value is represented by two consecutive delimiters. Table-structured files can be sorted or unsorted.

    • Documentum is document management software that provides management of document content and attributes, such as check-in, check-out, workflow, and version management. The Documentum product is a three-tier, client-server system built on top of a relational database. A Docbase is a Documentum repository that stores document content, attributes, relationships, versions, renditions, formats, work flow, and security. Documentum Query Language (DQL), an extended SQL dialect, is used to query Documentum data.

    • An Excel spreadsheet or workbook is a file created using the Microsoft Excel application and has a file extension of xls.

    • Basic Local Alignment Search Tool (BLAST) is a utility that is maintained by the National Center for Biotechnology Information (NCBI). BLAST is used to scan a nucleotide or amino acid sequence database for hits. A BLAST hit contains one or more high-scoring segment pairs (HSPs). A HSP is a pair of sequence fragments whose alignment is locally maximal and whose similarity score exceeds some threshold value. NCBI provides an executable, blastall, that is used to perform BLAST searches on BLAST-able data sources.

    • The Extensible Markup Language (XML) is a universal format for structured documents and data. XML files have a file extension of xml. Like HTML, XML makes use of tags for structuring data in the document.


Customers accessing federated data sources, using DB2 Relational Connect Version 7 to connect to non-IBM data sources, or DB2 Life Sciences Data Connect Version 7 should wait to upgrade to DB2 Version 8 until this functionality is available.

DB2 Version 8 supports federation among the IBM family of database products, including:

  • DB2 Universal Database (UDB) for Linux, UNIX, and Windows

  • DB2 for z/OS

  • DB2 for iSeries

  • IBM Informix IDS

  • IBM Informix XPS