In PostgreSQL, one and the same function name can be used for different functions as long as the number of arguments or their types differ. R, however, requires all function names to be distinct. PL/R deals with this by constructing the internal R function names as a concatenation of the string "PLR" with the object ID of the procedure's pg_proc. Thus, PostgreSQL functions with the same name and different argument types will be different R functions too. This is not normally a concern for a PL/R programmer, but it might be visible when debugging.
If a specific, known, function name is needed so that an R function can
be referenced by one or more PL/R functions, the
install_rcmd(text) command can be used.
See Chapter 5.