Application requester driver programs

An application requester driver (ARD) program is a type of exit program that enables SQL applications to access data managed by a database management system other than DB2 Universal Database™ for iSeries™.

An iSeries client calls the ARD program during the following operations:

• The package creation step of SQL precompiling, performed using the Create Structured Query Language Package (CRTSQLPKG) command or CRTSQLxxx commands, when the relational database (RDB) parameter matches the RDB name corresponding to the ARD program.
• Processing of SQL statements when the current connection is to an RDB name corresponding to the ARD program.

These calls allow the ARD program to pass the SQL statements and information about the statements to a remote relational database and return results back to the application requester (AR). The AR then returns the results to the application or the user. Access to relational databases accessed by ARD programs appear like access to DRDA^® application servers in the unlike environment.

The ARD program is registered in the system by use of the Add Relational Database Directory Entry (ADDRDBDIRE) command. One of the parameters that is specified is the library in which the program is located. For a system configured with independent auxiliary storage pools, the ARD program must reside in a library in the system database (a library that is part of the system ASP or a configured basic ASP).