Adding unique keys

These steps are part of the larger task of creating a table. When you complete the steps for adding unique keys, return to Creating a table.

To add unique keys:

1. In the Add Unique Key window, in the Available columns box, select the column or columns that you want to define as unique key columns. The columns that you select cannot allow null values, and cannot be LOB columns.

   You can define up to 64 columns to be unique key columns, and the sum of their lengths must not exceed 254.

   A unique key is a duplicate if it is the same as the primary key or a previously defined unique key. A duplicate unique key is ignored with a warning.

2. Click on the > push button to move the selected column or columns to the Unique key columns box.
3. Click Add to add the new unique key.
4. Repeat steps 1 through 3 to add another unique key to your table.
5. Click Close to close the Add Unique Key window.