a routine that is not in the compilation unit that calls it
a routine written in C or some other external language
A routine written in a language external to the database (for example, ), whose body is stored outside the database but whose name and parameters are registered in the system catalog tables.
In REXX, a program external to the user's program, language processor, or both. These routines can be written in any language (including REXX) that supports the system-dependent interfaces used by REXX to start it.
A function written in a third-generation language (3GL), such as C, and callable from within PL/SQL or SQL as if it were a PL/SQL function or procedure.
A procedure or function called from outside the program in which the routine is defined.
A routine defined in another compilation unit.