def METHOD_NAME(fdb):
    """
    overwrite any existing testDB file,
    and create a small DB with a few different tables.
    NOTE: tables should be the primary structure we use, but we can also
    insert single documents as needed.
    """
    # access the DB file.  this routine creates a new one every time
    if os.path.exists(fdb):
        os.remove(fdb)
    testDB = db.TinyDB(fdb)
    query = db.Query()
    # make a test record that will be added to the "_default" table.
    test_record = {"p1cal":{"ds":20, "cal":0.4056}}
    # use 'insert' the first time
    testDB.insert(test_record) 
    # use 'update' on subsequent times
    test_record = {"p1cal":{"ds":20, "cal1":0.4056, "cal2":123}}
    testDB.update(test_record)
    # search the DB for this key (returns a list)
    # access is through the first key, which is why it's nested
    rec_found = testDB.search(db.where("p1cal"))
    if len(rec_found) > 1:
        print("warning, multiple entries present")
    else:
        rec_found = rec_found[0]
    # ** Make a new table to hold a set of records. This is encouraged ** 
    # creates new if it doesn't exist, or appends if it does exist.
    # give it a key that is memorable with no spaces, commas, or periods.
    table = testDB.table("cal_pass1") 
    # be careful, this will add duplicates if you call it multiple times
    table.insert({"ds":3, "p1cal":0.40670})
    table.insert({"ds":4, "p1cal":0.51781})
    docid = table.insert({"ds":4, "p1cal":0.51781}) # <- avoid this mistake!
    table.remove(doc_ids=[docid]) 