Programming considerations for a distributed relational database application

 

Programming considerations for a distributed relational database application on the i5/OS^® operating system fall into two main categories: those that deal with a function that is supported on the local system and those that are a result of having to connect to other systems.

• Naming of distributed relational database objects
  SQL objects are created and maintained as i5/OS objects. You can use either of the two naming conventions in DB2 Universal Database™ for iSeries™ programming: system (*SYS) and SQL (*SQL).

• Connecting to a distributed relational database
  What makes a distributed relational database application distributed is its ability to connect to a relational database on another system.

• 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).

• Ending 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 a called stored procedure or user-defined function (UDF) to start commitment control on the i5/OS operating system.

• 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 i5/OS operating system converts the data automatically between other systems that use DRDA support.

• DDM files and SQL
  You can use i5/OS 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.

 

Parent topic:

Application development

 

Related reference

Tips: Designing distributed relational database applications