Prioritizing rule evaluation order

You modify the relative priority of a rule by moving it up or down in the Rules view.

In addition to sorting rules by name or priority, you can also modify a rule's priority in the Rules view of Developer Studio. Priority is indicated by a rule's position in the Rules view, relative to the position of other rules when you have sorted the rules by priority.

A rule's priority affects the order in which the MDEX Engine evaluates the rule. The MDEX Engine evaluates rules that are higher in the Rules view before those that are positioned lower. By increasing the priority of a rule, you increase the likelihood that the rule is triggered before another, and in turn, increase the likelihood that the rule promotes records before others.

It is important to consider rule priority in conjunction with the settings you specify in the Zone editor. For example, suppose a zone has Rule Limit set to three. If you have ten rules available for the zone, the MDEX Engine evaluates the rules, in the order they appear in the Rules view, and returns results from only the first three that have valid results. In addition, the Shuffle Rules check box on the Zone editor overrides the priority order you specify in the Rules view. When you check Shuffle Rules, the MDEX Engine randomly evaluates the rules associated with a zone.

If you set up rule groups, you can modify the priority of a rule within a group and modify the priority of a group with respect to other groups. For details, see Prioritizing rule groups.

To prioritize rules:

In the Rules view, click the Name column header to cycle the order of the rule sort so that the rules are displayed in priority order (you'll see Sorted by Priority in the lower left corner of the Rules view).
Select the rule whose priority you want to change and click the Up or Down buttons to move the rule to the desired position.