How to Create a Microsoft Access Field That Automatically Generates Numbers

You can create a field that automatically generates unique numbers for each record. AutoNumbers are the simplest way to set up primary keys, which are vital if you want to establish relationships among the various tables in your database. A primary key is a unique identifier for each record in the database; with a primary key, you can share record information across multiple tables. These instructions are for Microsoft Access 97.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Microsoft Access

1. Open a table in Design view.

2. Click in the field directly below the location where you want your new number field to appear. If you want to create a new field at the end, click in the first empty row.

3. Click on the Insert Row icon in the toolbar, or open the Insert menu and choose Row.

4. Click in the Field Names box, then name your field.

5. Click in the DataType field directly to the right. An arrow appears.

6. Click on the arrow. A menu of datatype choices appears.

7. Select AutoNumber.

8. Click in Format in the Field Properties window at the bottom of the screen. Select your preferred formats.

9. Save your table.

Tips & Warnings

• The property settings in the Field Properties window will assign incrementing numbers as the default. If you want to create random auto-numbers, change the New Values property to Random.
• MS Access can assign three types of primary numbers. They are AutoNumber, single-field, and multiple-field.
• If you have not assigned a primary key when you create a table, MS Access will remind you when you close the table.