CounterBook: 2953 rows, 13 columns

1. Redundancy: how often one fact is written down
   name of outlet O01:   1312 times
   price of S0001:       1368 times
   phone of C0094:       62 times

2. Update anomaly: C0094 gets a new phone; the clerk fixes ten rows
   C0094 phone 0811-0000-9999: 10 rows
   C0094 phone 0881-0000-0172: 52 rows

3. Update anomaly: wash-fold goes up to Rp 9.000/kg
   S0001 rows where price x unit <> amount charged, before: 12
   the same, after the price change:                        1368

4. Deletion anomaly: remove the bills of one-visit customers
   18 customers vanished with their only bill.
   C0063 rows left in CounterBook: 0   rows in the real Customer table: 1

5. Insertion anomaly: a new service with no bill yet
   customers with no bill at all (cannot appear in CounterBook): 3
   row for S0013 stored with bill = None and cust_id = None
