If nodes and element connectivity are absent from the Nastran results file, locate and comment out the following line in the input deck and re-run the job:
PARAM,OGEOM,NO
The parameter instructs Nastran to exclude model data from the results file.
If model data is to be included in the output file, either comment out (precede with dollar sign) or delete the command.
Typically, the Patran .db file already has the geometry loaded and hence it needs only the results from the file.