Your index is automatically saved in the database when you save your table or database diagram. The index is available for modification as soon as you create it.
To display and update index definitions
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Open the Table Designer for the table whose index you want to modify, right-click in the Table Designer, and choose Properties from the shortcut menu.
Your changes are saved to the database when you save the table or diagram.
Note that you can also manage indexes on some views. For more information, see Indexed Views.