Programming considerations for a distributed relational database application

Programming considerations for a distributed relational database application on an iSeries™ server fall into two main categories: those that deal with a function that is supported on the local server and those that are a result of having to connect to other servers.

• Naming of distributed relational database objects
  SQL objects are created and maintained as iSeries server objects.
• Connect to a distributed relational database
  What makes a distributed relational database application distributed is its ability to connect to a relational database on another server.
• SQL specific to distributed relational database and SQL CALL
  During the precompile process of a distributed DB2 Universal Database™ for iSeries application, the i5/OS™ licensed program might build SQL packages to be run on an application server (AS).
• End DRDA units of work
  You should be careful about ending SQL programs with uncommitted work. When a program ends with uncommitted work, the connection to the relational database remains active.
• Stored procedures, user-defined functions, and commitment control
  When an application such as Interactive SQL is running without commitment control active (COMMIT(*NONE)) over a DRDA^® connection, it is possible for an invoked stored procedure or user-defined function (UDF) to start commitment control on an iSeries server.
• Coded character set identifier
  Support for the national language of any country requires the proper handling of a minimum set of characters.
• Other DRDA data conversion
  Sometimes, when you are doing processing on a remote system, your program might need to convert the data from one system so that it can be used on the other. Distributed Relational Database Architecture™ (DRDA^®) support on the iSeries server converts the data automatically between other systems that use DRDA^® support.
• DDM files and SQL
  You can use iSeries distributed data management (DDM) support to help you do some distributed relational database tasks within a program that also uses SQL distributed relational database support.