Handling Recursion In Triggers

What Is Recursion In Triggers? 

Recursion in Triggers happens when a Trigger is called repeatedly, resulting in an infinite loop.

To counter recursion, we need to:

1. Create another class called RecursiveTriggerHandler.
2. Make use of “Static” variables.

Example:

trigger BranchTrigger on Branch__c(before update) {
            if (RecursiveTriggerHandler.isFirstRun) {
                RecursiveTriggerHandler.isFirstRun = false;
                // Call Helper Class method 
                BranchTriggerHelper.firstMethod(Trigger.new);
            }

The first instance of the Trigger is run and if this variable is true, the logic in the Helper Class executes.

Other Best Practices for writing triggers:

1. Always create only one Trigger per object.
2. Create logic-less Triggers and use Helper Class Design Pattern in which the helper class will contain all the logic.
3. Create context-specific handler methods in the Helper Class.
4. Bifurcate “insert” and “update” Trigger logic contexts and create two different methods in the Trigger’s helper class.

 trigger PositonTrigger on Position__c(after insert, after update) {
            if (Trigger.isAfter && Trigger.isInsert) {
                PositionTriggerHandler.handleAfterInsert(Trigger.new);
            } else if (Trigger.isAfter && Trigger.isUpdate) {
                PositionTriggerHandler.handleAfterUpdate(Trigger.new, Trigger.old);
            }
        }