How to Prevent Duplicate Values in a Microsoft Access Database

You can keep your Microsoft Access database free of confusing clutter by preventing duplicate values. These instructions are for Access 97.

Things You'll Need

• Microsoft Access

Instructions

Preventing Duplicate Entries in a Combination of Fields

1. Open the table in Design view.

2. Click Indexes on the toolbar, or open the View menu and choose Index.

3. Type a name for the index in the Index Name column.

4. Go to the Field Name column and click the arrow.

5. Select the first field for the index.

6. Repeat, selecting as many fields as necessary.

7. Leave the Index window open.

8. Click on the new index name at the top.

9. At the bottom of the screen, click the Unique property box.

10. Set it to Yes.

Preventing Duplicate Values in a Field

1. Understand that this method will prevent duplicate values from being entered in a field. For example, you might want to ensure that you enter a name only once in your address book.

2. Open a table in Design view.

3. In the upper part of the screen, click on the field that you want to prevent duplicate entries in.

4. In the lower part of the screen, click the Indexed property box and select Yes (No Duplicates).