`Importing data from /home/ubuntu/code/discogs-xml2db/csv-dir/release_company.csv
Traceback (most recent call last):
  File "postgresql/importcsv.py", line 42, in <module>
    load_csv(os.path.abspath(filename), db)
  File "postgresql/importcsv.py", line 33, in load_csv
    cursor.copy_expert(q, fp)
psycopg2.errors.NotNullViolation: null value in column "company_id" violates not-null constraint
DETAIL:  Failing row contains (13551, 3759, null, Infinite Jazz Recordings, 14, Copyright (c), null).
CONTEXT:  COPY release_company, line 13552: "3759,,Infinite Jazz Recordings,14,Copyright (c),"