What is an UDFT?
Datacom PTF RO89483 is making reference to UDFT.
Release: 14.0 and above
An SQL User-Defined Function Table (UDFT) is similar to an External Procedure but is used in a query as if it were a normal table.
A UDFT, like a normal table, is invoked when its name is referenced.
A UDFT is not called by a program or trigger.
Unlike a normal table, however, a UDFT is read-only.
Unlike an External Procedure, a UDFT returns a table row, whose columns are declared in the CREATE FUNCTION statement in the RETURNS clause. ...
UDFT was introduced with Datacom Version 14.0 via PTF RO40578 for some Datacom/AD product usage. It is now fully available and documented for Datacom Version 15.0 and above.
See the Datacom 15.1 documentation section SQL User Defined Function Table (UDFT)