- 1). Open your Microsoft Access database.
- 2). Right click your table in the Navigation Pane on the left side of the screen. If it's not expanded, press the double arrow located underneath the menu bars to expand it.
- 3). Select "Design View".
- 4). Select the field name you want to use as your primary key. If you want to choose multiple fields, press and hold the "Ctrl" key while selecting the fields.
- 5). Choose "Primary Key" from the "Tools" group in the "Design" tab.
- 6). Check that the correct field(s) have been set by looking for a key symbol beside the field name(s).
- 7). Press "Ctrl" and "S" to save your changes.
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