When *DBMS400 is used with an Entry, the ITP iSeries Connection will perform exactly the function described in the "Intended working of Key selection" and "Intended working of Data retrieval". An advantage of using *DBMS400 is that no separate program object is needed for an Entry. Disadvantages of *DBMS400 are that there is no way to change ore adapt the working of an Entry to fit some special needs and *DBMS400 can only be used with generated Entries.
The big advantage of the program interface is that the program can be changed to do virtually anything as long as the parameter and ISNDDTA interface requirements are satisfied. A disadvantage of the program interface is that the program and its source are two extra objects that need to be maintained. The default libraries to store the program and its source in are the Object library and the Source library of the DID-source, refer to Work with DID-sources.