What is recursion problem in Salesforce Trigger? How to troubleshoot it?

Hello Chanchal,

Recursion in trigger means we are calling same method infinite times, this could happen when we have event 'update' in Account(let say) and in last we using DML query which Update in Account, therefore trigger undergoes to recursion.

Avoiding a recrusion problem in trigger is easy. There are two methods we can use it to avoid recursion:-

1. Create an Apex class with 'static' variable of boolean type and changes its value once update is done.
2. Create an Apex class with 'static' variable of 'Set' type which store unique IDs of update records enter and check in trigger that if IDs exist in Set then don't do updates.

Thanks.

Avoiding Recursive Triggers:

Recursion occurs when the same code is executed again and again. It can lead to an infinite loop and which can result in governor limit sometime. Sometime it can also result in unexpected output.

It is very common to have recursion in the trigger which can result in unexpected output or some error. So we should write code in such a way that it does not result to recursion. But sometime we are left with no choice.

For example, we may come across a situation where in a trigger we update a field which in result invoke a workflow. The workflow contains one field update on the same object. So trigger will be executed two times. It can lead us to unexpected output.

Another example is our trigger fires on after update, and it updates some related object, and there is one more trigger on a related object which updates child object. So it can result from too infinite loop.

To avoid the situation of the recursive call, make sure your trigger is getting executed only one time. To do so, you can create a class with a static boolean variable with default value true.

In the trigger, before executing your code keep a check that the variable is true or not.

Once you check to make the variable false.

As an example let says you have the following trigger on contact:

trigger recursiveTrigger on Contact (after update) {
Id recordId ;
for(contact con : trigger.new){
recordId = con.id;
}
Contact conRec =[select id,name,email from contact where id !=: recordId limit 1];

conRec.email = 'testemail@kmail.com';
update conRec;
}
}

thanks.

Hi,

A recursive trigger is one that performs an action, such as an update or insert, which invokes itself owing to,  say something like an update it performs.

eg in a before trigger, if you select some records and update them, the trigger will invoke itself.

Hope this helps.

• This reply was modified 6 years, 6 months ago by  shariq.