Optional. Enter the second key part of a when condition rule to further qualify which indexes are created by this rule, or an expression resulting in a Boolean value.The system uses the Applies To key part of this Declare Index rule as the Applies To key part of the when condition.
The system evaluates this rule or expression each time an instance of the Applies To class is saved by any requestor. Both outcomes — true and false — may create or remove indexes:
•If the condition or expression is false, no Index- instances (from that Applies To instance) must be present. None are added. Any existing Index- instances are deleted.
•If the condition or expression evaluates to true, Index- instances appropriate to this Declare Index rule are added. Previously created Index- instances may be deleted.