Chapter 18: Rose Data Modeler

Adding Indexes

An index is modeled as a key constraint in a table. An index is a structure that allows for quick searches of a table. One or more columns are used for an index; when a search is performed, only those columns are searched.

To add an index:

1.

Open the table or Column Specification window.

2.

Select the Key Constraints tab.

3.

Click New.

4.

Set the Type to Index.

5.

In the Columns list box, select the column(s) that will be used in the index. Use the Add button to move the selected columns to the Key Columns list box.

6.

Select the Deferrable check box (Oracle and SQL 92 only) if you want to make the constraint deferred. A nondeferred constraint will run at the end of a statement. A deferred, initially immediate constraint will run at the beginning of a transaction. A deferred, initially deferred constraint will run at the end of a transaction.

7.

Select the Unique check box (Index constraint) if the index is unique.

8.

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