To find duplicated values in one or more column, use the Tools > Find Duplicates command. In the displayed dialog box you can specify:

• whether to search for duplicates within the entire table or the current record set
• which record order is to be used for displaying: the physical table order or any sort order
• up to 100 fields to be used as a duplicate key
• how to display the results:
  • the first (entered in the table) records from each group of duplicates,
  • the last (entered in the table) records from each group of duplicates,
  • all records from each group of duplicates except the first one,
  • all records from each group of duplicates except the last one.