dm to anotherRetrieve the name of the column marked as foreign key, pointing from one table of a dm to another
cdm_get_fk(dm, table, ref_table)A dm object.
A table in the dm
The table which is referenced from table.
Other foreign key functions: cdm_add_fk,
cdm_enum_fk_candidates,
cdm_get_all_fks, cdm_has_fk,
cdm_rm_fk